2025-07-10 18:04:09 +02:00
305 changed files with 17176 additions and 26476 deletions
--- a/.appveyor.yml
+++ b/.appveyor.yml
@ -1,81 +0,0 @@
 version: 1.6.x-{build}
 branches:
  except:
    - /libpng[0-1][0-8]/
    - /v[0-1][.][0-8][.][0-9]+/
 image:
  - Visual Studio 2022
 shallow_clone: true
 environment:
  matrix:
    - TOOLCHAIN: vstudio
      AUTOMATION: cmake
      ARCH: x86
    - TOOLCHAIN: vstudio
      AUTOMATION: cmake
      ARCH: x64
    - TOOLCHAIN: vstudio
      AUTOMATION: cmake
      ARCH: arm64
    - TOOLCHAIN: llvm
      AUTOMATION: cmake
      ARCH: x64
    - TOOLCHAIN: msys2
      AUTOMATION: cmake
      ARCH: i686
    - TOOLCHAIN: msys2
      AUTOMATION: cmake
      ARCH: x86_64
    - TOOLCHAIN: msys2
      AUTOMATION: configure
      ARCH: i686
    - TOOLCHAIN: msys2
      AUTOMATION: configure
      ARCH: x86_64
    - TOOLCHAIN: msys2
      AUTOMATION: makefiles
      ARCH: i686
    - TOOLCHAIN: msys2
      AUTOMATION: makefiles
      ARCH: x86_64
 install:
  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
  - 'if "%TOOLCHAIN%"=="vstudio" C:\tools\vcpkg\vcpkg.exe integrate install'
  - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe install zlib:%ARCH%-windows'
  - 'if "%TOOLCHAIN%"=="llvm" C:\tools\vcpkg\vcpkg.exe integrate install'
  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" C:\msys64\usr\bin\pacman.exe -S --noconfirm mingw-w64-%ARCH%-cmake mingw-w64-%ARCH%-ninja'
 before_build:
  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_GENERATOR=Visual Studio 17 2022'
  - 'if "%TOOLCHAIN%"=="vstudio" set CI_CMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x86" set CI_CMAKE_GENERATOR_PLATFORM=Win32'
  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="x64" set CI_CMAKE_GENERATOR_PLATFORM=x64'
  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_GENERATOR_PLATFORM=ARM64'
  - 'if "%TOOLCHAIN%"=="vstudio" if "%ARCH%"=="arm64" set CI_CMAKE_VARS=-DPNG_TESTS=0'
  - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_GENERATOR=Ninja'
  - 'if "%TOOLCHAIN%"=="llvm" set CI_CMAKE_TOOLCHAIN_FILE=C:\tools\vcpkg\scripts\buildsystems\vcpkg.cmake'
  - 'if "%TOOLCHAIN%"=="llvm" set CI_CC=clang'
  - 'if "%TOOLCHAIN%"=="msys2" set CI_CMAKE_GENERATOR=Ninja'
  - 'if "%TOOLCHAIN%"=="msys2" set CI_CC=gcc'
  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="i686" set MSYSTEM=MINGW32'
  - 'if "%TOOLCHAIN%"=="msys2" if "%ARCH%"=="x86_64" set MSYSTEM=MINGW64'
  - 'set CI_CMAKE_BUILD_FLAGS=-j2'
  - 'set CI_CTEST_FLAGS=-j2'
  - 'set CI_MAKE_FLAGS=-j2'
  - 'set CI_MAKEFILES=scripts/makefile.gcc scripts/makefile.msys scripts/makefile.std'
 build_script:
  - 'if "%TOOLCHAIN%"=="vstudio" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
  - 'if "%TOOLCHAIN%"=="llvm" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="cmake" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_cmake.sh"'
  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="configure" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_configure.sh"'
  - 'if "%TOOLCHAIN%"=="msys2" if "%AUTOMATION%"=="makefiles" C:\msys64\usr\bin\bash.exe -l "%APPVEYOR_BUILD_FOLDER%\ci\ci_verify_makefiles.sh"'
 cache:
  - 'C:\tools\vcpkg\installed'
  - 'C:\msys64\var\cache\pacman'
--- a/.cmake-format.yaml
+++ b/.cmake-format.yaml
@ -1,94 +0,0 @@
 # https://pypi.org/project/cmakelang
 # https://github.com/cheshirekow/cmake_format
 # ----------------------
 # Options for formatting
 # ----------------------
 # How wide to allow formatted cmake files
 # TODO: Reflow the CMake files to allow setting the maximum line width to 100.
 line_width: 255
 # How many spaces to tab for indent
 tab_size: 2
 # If true, lines are indented using tab characters (utf-8 0x09) instead of
 # <tab_size> space characters (utf-8 0x20). In cases where the layout would
 # require a fractional tab character, the behavior of the fractional
 # indentation is governed by <fractional_tab_policy>
 use_tabchars: false
 # If <use_tabchars> is True, then the value of this variable indicates how
 # fractional indentions are handled during whitespace replacement. If set to
 # 'use-space', fractional indentation is left as spaces (utf-8 0x20). If set
 # to `round-up` fractional indentation is replaced with a single tab character
 # (utf-8 0x09) effectively shifting the column to the next tabstop
 fractional_tab_policy: "use-space"
 # Enable comment markup parsing and reflow
 enable_markup: false
 # -------------------
 # Options for linting
 # -------------------
 # Lint codes to disable
 disabled_codes: [
  # TODO:
  # Reconcile the CMake variable names with the patterns below, then
  # re-enable the "invalid variable name XXX" messages.
  "C0103",
  # TODO:
  # Add brief COMMENT arguments to the `add_custom_target` commands.
  "C0113",
 ]
 # Regular expression pattern describing valid function names
 function_pattern: "[0-9a-z_]+"
 # Regular expression pattern describing valid macro names
 macro_pattern: "[0-9A-Z_]+"
 # Regular expression pattern describing valid names for variables with global
 # (cache) scope
 global_var_pattern: "[A-Z][0-9A-Z_]+"
 # Regular expression pattern describing valid names for variables with global
 # scope (but internal semantic)
 internal_var_pattern: "_[A-Z][0-9A-Z_]+"
 # Regular expression pattern describing valid names for variables with local
 # scope
 local_var_pattern: "[a-z][a-z0-9_]+"
 # Regular expression pattern describing valid names for privatedirectory
 # variables
 private_var_pattern: "_[0-9a-z_]+"
 # Regular expression pattern describing valid names for public directory
 # variables
 public_var_pattern: "[A-Z][0-9A-Z_]+"
 # Regular expression pattern describing valid names for function/macro
 # arguments and loop variables.
 argument_var_pattern: "[a-z][a-z0-9_]+"
 # Regular expression pattern describing valid names for keywords used in
 # functions or macros
 keyword_pattern: "[A-Z][0-9A-Z_]+"
 # In the heuristic for C0201, how many conditionals to match within a loop in
 # before considering the loop a parser
 max_conditionals_custom_parser: 2
 # Require at least this many newlines between statements;
 # require no more than this many newlines between statements;
 # etc.
 min_statement_spacing: 1
 max_statement_spacing: 2
 max_returns: 6
 max_branches: 12
 max_arguments: 5
 max_localvars: 15
 max_statements: 50
--- a/.editorconfig
+++ b/.editorconfig
@ -1,55 +0,0 @@
 # https://editorconfig.org
 root = true
 [*]
 charset = utf-8
 insert_final_newline = true
 trim_trailing_whitespace = true
 [*.txt]
 indent_size = unset
 indent_style = space
 [*.[chS]]
 indent_size = 3
 indent_style = space
 max_doc_length = 80
 max_line_length = 80
 [*.dfa]
 indent_size = 3
 indent_style = space
 max_doc_length = 80
 max_line_length = 80
 [*.awk]
 indent_size = 3
 indent_style = space
 max_doc_length = 80
 max_line_length = 100
 [*.cmake]
 indent_size = 2
 indent_style = space
 max_doc_length = 80
 max_line_length = 100
 [*.sh]
 indent_size = 4
 indent_style = space
 max_doc_length = 100
 max_line_length = 100
 [{Makefile.in,aclocal.m4,ltmain.sh}]
 indent_size = unset
 indent_style = unset
 insert_final_newline = unset
 max_doc_length = unset
 max_line_length = unset
 trim_trailing_whitespace = unset
 [COMMIT_EDITMSG]
 indent_style = space
 max_doc_length = unset
 max_line_length = 72
--- a/.editorconfig-checker.json
+++ b/.editorconfig-checker.json
@ -1,9 +0,0 @@
 {
  "Disable": {
    "IndentSize": true
  },
  "Exclude": [
    ".git/",
    "out/"
  ]
 }
--- a/.github/workflows/lint.yml
+++ b/.github/workflows/lint.yml
@ -1,31 +0,0 @@
 name: Linting libpng
 on:
  push:
    branches:
      - libpng16
      - libpng18
  pull_request:
    branches:
      - libpng16
      - libpng18
 jobs:
  lint:
    runs-on: ubuntu-latest
    timeout-minutes: 5
    steps:
      - name: Set up the cache
        uses: actions/cache@v4
        with:
          path: ~/.cache/pip
          key: ${{ runner.os }}-pip-${{ hashFiles('**/pip.txt') }}
          restore-keys: ${{ runner.os }}-pip-
      - name: Install yamllint
        run: pip install yamllint
      - name: Install editorconfig-checker
        uses: editorconfig-checker/action-editorconfig-checker@main
      - name: Check out the code
        uses: actions/checkout@v4
      - name: Run the linting script
        run: bash ./ci/ci_lint.sh
--- a/.gitignore
+++ b/.gitignore
@ -1,159 +0,0 @@
 # Prerequisites
 *.d
 # Precompiled headers
 *.gch
 *.pch
 # Object files
 *.slo
 *.lo
 *.o
 *.obj
 # Linker output files
 *.exp
 *.ilk
 *.map
 # Compiled dynamic libraries
 *.dll
 *.dylib
 *.so
 *.so.*
 # Compiled static libraries
 *.a
 *.la
 *.lai
 *.lib
 # Compiled executables
 *.app/
 *.exe
 a.out
 # Debug files
 *.dSYM/
 *.idb
 *.pdb
 *.su
 # Tag files
 TAGS
 .TAGS
 !TAGS/
 tags
 .tags
 !tags/
 gtags.files
 GTAGS
 GRTAGS
 GPATH
 GSYMS
 cscope.files
 cscope.out
 cscope.*.out
 # Text editing and text processing artifacts
 \#*\#
 .\#*
 [._]*.sw[a-p]
 [._]sw[a-p]
 *.bak
 *.orig
 *.rej
 *.tmp
 *~
 # IDE files and directories
 ## Eclipse
 .cproject/
 .project/
 .settings/
 ## Embarcadero RAD Studio
 *.cbproj.*
 __recovery/
 ## JetBrains
 .idea/
 ## NetBeans
 nbbuild/
 nbdist/
 nbproject/
 ## Visual Studio
 .vs/
 ### Visual Studio user files
 *.rsuser
 *.sln.docstates
 *.suo
 *.user
 *.userprefs
 ### Visual Studio cache files (for older versions)
 *.aps
 *.ncb
 *.opensdf
 *.sdf
 *.VC.db
 *.VC.opendb
 ipch/
 ## Visual Studio Code
 .vscode/*
 !.vscode/extensions.json
 !.vscode/launch.json
 !.vscode/settings.json
 !.vscode/tasks.json
 ## (Various)
 *.*cache
 *.cache*
 [._]*_history
 .history/
 [Bb]ackup*/
 # Build, test and CI output directories
 *[Dd]ebug/
 [Dd]ebug*/
 *[Rr]elease/
 [Rr]elease*/
 [._]build*/
 /[Bb]uild*/
 /[Oo]ut/
 # Libpng configuration and auxiliary build artifacts
 *.out
 *out.png
 [._]deps/
 [._]libs/
 .dirstamp
 /Makefile
 /autom4te.cache/
 /config*~
 /config.h
 /config.log
 /config.status
 /install*~
 /libpng*-config
 /libpng*.pc
 /libpng.vers
 /libtool
 /stamp-h1
 CMake*.json
 !CMakePresets.json
 CMakeLists.txt.*
 pnglibconf.[ch]
 pnglibconf.dfn
 pnglibconf.pre
 pngprefix.h
 # Libpng test programs, scripts and artifacts
 /test-suite.log
 /tests/*.log
 /tests/*.trs
 /png-fix-itxt
 /pngcp
 /pngfix
 /pngimage
 /pngstest
 /pngtest
 /pngunknown
 /pngvalid
 /timepng
--- a/.yamllint.yml
+++ b/.yamllint.yml
@ -1,7 +0,0 @@
 extends: default
 rules:
  document-start: disable
  document-end: disable
  line-length: disable
  truthy:
    check-keys: false
--- a/44
+++ b/44
@ -1,13 +1,5 @@
-libpng 1.6.51.git
+libpng 1.6.37 - April 14, 2019
-=================
+==============================
 This is a development version, not intended to be a public release.
 It will be replaced by a public release, or by another development
 version, at a later time.
 libpng 1.6.50 - July 1, 2025
 ============================
 This is a public release of libpng, intended for use in production code.
@ -17,13 +9,13 @@ Files available for download
 Source files with LF line endings (for Unix/Linux):
- * libpng-1.6.50.tar.xz (LZMA-compressed, recommended)
+ * libpng-1.6.37.tar.xz (LZMA-compressed, recommended)
- * libpng-1.6.50.tar.gz (deflate-compressed)
+ * libpng-1.6.37.tar.gz
 Source files with CRLF line endings (for Windows):
- * lpng1650.7z (LZMA-compressed, recommended)
+ * lp1637.7z (LZMA-compressed, recommended)
- * lpng1650.zip (deflate-compressed)
+ * lp1637.zip
 Other information:
@ -33,18 +25,20 @@ Other information:
 * TRADEMARK.md
-Changes from version 1.6.49 to version 1.6.50
+Changes since the previous public release (version 1.6.36)
---------------------------------------------
+----------------------------------------------------------
- * Improved the detection of the RVV Extension on the RISC-V platform.
+ * Fixed a use-after-free vulnerability (CVE-2019-7317) in png_image_free.
-   (Contributed by Filip Wasil)
+ * Fixed a memory leak in the ARM NEON implementation of png_do_expand_palette.
- * Replaced inline ASM with C intrinsics in the RVV code.
+ * Fixed a memory leak in pngtest.c.
-   (Contributed by Filip Wasil)
+ * Fixed two vulnerabilities (CVE-2018-14048, CVE-2018-14550) in
- * Fixed a decoder defect in which unknown chunks trailing IDAT, set
+   contrib/pngminus; refactor.
-   to go through the unknown chunk handler, incorrectly triggered
+ * Changed the license of contrib/pngminus to MIT; refresh makefile and docs.
-   out-of-place IEND errors.
+   (Contributed by Willem van Schaik)
-   (Contributed by John Bowler)
+ * Fixed a typo in the libpng license v2.
- * Fixed the CMake file for cross-platform builds that require `libm`.
+   (Contributed by Miguel Ojeda)
 * Added makefiles for AddressSanitizer-enabled builds.
 * Cleaned up various makefiles.
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
--- a/39
+++ b/39
@ -4,9 +4,7 @@ PNG REFERENCE LIBRARY AUTHORS
 This is the list of PNG Reference Library ("libpng") Contributing
 Authors, for copyright and licensing purposes.
 * Adam Richter
 * Andreas Dilger
 * Chris Blume
 * Cosmin Truta
 * Dave Martindale
 * Eric S. Raymond
@ -17,17 +15,12 @@ Authors, for copyright and licensing purposes.
 * James Yu
 * John Bowler
 * Kevin Bracey
 * Lucas Chollet
 * Magnus Holmgren
 * Mandar Sahastrabuddhe
 * Manfred Schlaegl
 * Mans Rullgard
 * Matt Sarett
 * Mike Klein
 * Pascal Massimino
 * Paul Schmidt
 * Philippe Antoine
 * Qiang Zhou
 * Sam Bushell
 * Samuel Williams
 * Simon-Pierre Cadieux
@ -37,30 +30,16 @@ Authors, for copyright and licensing purposes.
 * Vadim Barkov
 * Willem van Schaik
 * Zhijie Liang
 * Apple Inc.
    - Zixu Wang (王子旭)
 * Arm Holdings
-    - Richard Townsend
+   - Richard Townsend
- * Google LLC
+ * Google Inc.
-    - Dan Field
+   - Matt Sarett
-    - Dragoș Tiselice
+   - Mike Klein
    - Leon Scroggins III
    - Matt Sarett
    - Mike Klein
    - Sami Boukortt
    - Wan-Teh Chang
 * Loongson Technology Corporation Ltd.
    - GuXiWei (顾希伟)
    - JinBo (金波)
    - ZhangLixia (张利霞)
 * Samsung Group
    - Filip Wasil
 The build projects, the build scripts, the test scripts, and other
-files in the "projects", "scripts" and "tests" directories, have
+files in the "projects", "scripts" and "tests" directories, have other
-other copyright owners, but are released under the libpng license.
+copyright owners, but are released under the libpng license.
-Some files in the "ci" and "contrib" directories, as well as some
+Some files in the "contrib" directory, and some tools-generated files
-of the tools-generated files that are distributed with libpng, have
+that are distributed with libpng, have other copyright owners, and are
-other copyright owners, and are released under other open source
+released under other open source licenses.
 licenses.
--- a/201
+++ b/201
@ -204,7 +204,7 @@ Version 0.97 [January, 1998]
  Added simple sRGB support (Glenn R-P)
  Easier conditional compiling, e.g.,
    define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
-    all configurable options can be selected from command line instead
+    all configurable options can be selected from command-line instead
    of having to edit pngconf.h (Glenn R-P)
  Fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
  Added more conditions for png_do_background, to avoid changing
@ -942,7 +942,7 @@ Version 1.0.8 [July 24, 2000]
 Version 1.0.9beta1 [November 10, 2000]
  Fixed typo in scripts/makefile.hpux
  Updated makevms.com in scripts and contrib/* and contrib/* (Martin Zinser)
-  Fixed sequence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
+  Fixed seqence-point bug in contrib/pngminus/png2pnm (Martin Zinser)
  Changed "cdrom.com" in documentation to "libpng.org"
  Revised pnggccrd.c to get it all working, and updated makefile.gcmmx (Greg).
  Changed type of "params" from voidp to png_voidp in png_read|write_png().
@ -2295,7 +2295,7 @@ Version 1.4.0beta58 [May 14, 2009]
  Clarified usage of sig_bit versus sig_bit_p in example.c (Vincent Torri)
 Version 1.4.0beta59 [May 15, 2009]
-  Reformatted sources in libpng style (3-space indentation, comment format)
+  Reformated sources in libpng style (3-space intentation, comment format)
  Fixed typo in libpng docs (PNG_FILTER_AVE should be PNG_FILTER_AVG)
  Added sections about the git repository and our coding style to the
    documentation
@ -2661,7 +2661,7 @@ Version 1.4.1beta06 [January 28, 2010]
 Version 1.4.1beta07 [February 6, 2010]
  Folded some long lines in the source files.
-  Added definable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
+  Added defineable PNG_USER_CHUNK_CACHE_MAX, PNG_USER_CHUNK_MALLOC_MAX,
    and a PNG_USER_LIMITS_SUPPORTED flag.
  Eliminated use of png_ptr->irowbytes and reused the slot in png_ptr as
    png_ptr->png_user_chunk_malloc_max.
@ -3886,7 +3886,7 @@ Version 1.6.0beta06 [January 24, 2012]
 Version 1.6.0beta07 [January 28, 2012]
  Eliminated Intel icc/icl compiler warnings. The Intel (GCC derived)
    compiler issues slightly different warnings from those issued by the
-    current versions of GCC. This eliminates those warnings by
+    current vesions of GCC. This eliminates those warnings by
    adding/removing casts and small code rewrites.
  Updated configure.ac from autoupdate: added --enable-werror option.
    Also some layout regularization and removal of introduced tab characters
@ -3919,7 +3919,7 @@ Version 1.6.0beta08 [February 1, 2012]
    version checking to configure.ac
  Improved pngstest speed by not doing redundant tests and add const to
    the background parameter of png_image_finish_read. The --background
-    option is now done automagically only when required, so that command-line
+    option is now done automagically only when required, so that commandline
    option no longer exists.
  Cleaned up pngpriv.h to consistently declare all functions and data.
    Also eliminated PNG_CONST_DATA, which is apparently not needed but we
@ -4052,7 +4052,7 @@ Version 1.6.0beta16 [March 6, 2012]
    (in fact this is harmless, but the PNG data produced may be sub-optimal).
 Version 1.6.0beta17 [March 10, 2012]
-  Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition.
+  Fixed PNG_LIBPNG_BUILD_BASE_TYPE definition. 
  Reject all iCCP chunks after the first, even if the first one is invalid.
  Deflate/inflate was reworked to move common zlib calls into single
    functions [rw]util.c.  A new shared keyword check routine was also added
@ -4962,7 +4962,7 @@ Version 1.6.13beta01 [July 4, 2014]
  Changed "if defined(__ARM_NEON__)" to
    "if (defined(__ARM_NEON__) || defined(__ARM_NEON))" (James Wu).
  Fixed clang no-warning builds: png_digit was defined but never used.
-
+    
 Version 1.6.13beta02 [July 21, 2014]
  Fixed an incorrect separator ("/" should be "\") in scripts/makefile.vcwin32
    (bug report from Wolfgang S. Kechel).  Bug was introduced in libpng-1.6.11.
@ -5453,7 +5453,7 @@ Version 1.6.21beta01 [December 11, 2015]
 Version 1.6.21beta02 [December 14, 2015]
  Moved png_check_keyword() from pngwutil.c to pngset.c
  Removed LE/BE dependencies in pngvalid, to 'fix' the current problem
-    in the BigEndian tests by not testing it, making the BE code the same
+    in the BigEndian tests by not testing it, making the BE code the same 
    as the LE version.
  Fixes to pngvalid for various reduced build configurations (eliminate unused
    statics) and a fix for the case in rgb_to_gray when the digitize option
@ -5517,7 +5517,7 @@ Version 1.6.22beta03 [March 9, 2016]
  Added a common-law trademark notice and export control information
    to the LICENSE file, png.h, and the man page.
  Restored "& 0xff" in png_save_uint_16() and png_save_uint_32() that
-    were accidentally removed from libpng-1.6.17.
+    were accidentally removed from libpng-1.6.17. 
  Changed PNG_INFO_cHNK and PNG_FREE_cHNK from 0xnnnn to 0xnnnnU in png.h
    (Robert C. Seacord).
  Removed dubious "#if INT_MAX" test from png.h that was added to
@ -5927,7 +5927,7 @@ Version 1.6.32beta03 [August 2, 2017]
    (Bug report from the OSS-fuzz project).
 Version 1.6.32beta04 [August 2, 2017]
-  Replaced local eXIf_buf with info_ptr->eXIf_buf in png_handle_eXIf().
+  Replaced local eXIf_buf with info_ptr-eXIf_buf in png_handle_eXIf().
  Update libpng.3 and libpng-manual.txt about eXIf functions.
 Version 1.6.32beta05 [August 2, 2017]
@ -5950,7 +5950,7 @@ Version 1.6.32beta09 [August 3, 2017]
  Require cmake-2.8.8 in CMakeLists.txt. Revised symlink creation,
    no longer using deprecated cmake LOCATION feature (Clifford Yapp).
  Fixed five-byte error in the calculation of IDAT maximum possible size.
-
+  
 Version 1.6.32beta10 [August 5, 2017]
  Moved chunk-length check into a png_check_chunk_length() private
    function (Suggested by Max Stepin).
@ -6103,183 +6103,6 @@ Version 1.6.37 [April 14, 2019]
  Added makefiles for AddressSanitizer-enabled builds.
  Cleaned up various makefiles.
 Version 1.6.38 [September 14, 2022]
  Added configurations and scripts for continuous integration.
  Fixed various errors in the handling of tRNS, hIST and eXIf.
  Implemented many stability improvements across all platforms.
  Updated the internal documentation.
 Version 1.6.39 [November 20, 2022]
  Changed the error handler of oversized chunks (i.e. larger than
    PNG_USER_CHUNK_MALLOC_MAX) from png_chunk_error to png_benign_error.
  Fixed a buffer overflow error in contrib/tools/pngfix.
  Fixed a memory leak (CVE-2019-6129) in contrib/tools/pngcp.
  Disabled the ARM Neon optimizations by default in the CMake file,
    following the default behavior of the configure script.
  Allowed configure.ac to work with the trunk version of autoconf.
  Removed the support for "install" targets from the legacy makefiles;
    removed the obsolete makefile.cegcc.
  Cleaned up the code and updated the internal documentation.
 Version 1.6.40 [June 21, 2023]
  Fixed the eXIf chunk multiplicity checks.
  Fixed a memory leak in pCAL processing.
  Corrected the validity report about tRNS inside png_get_valid().
  Fixed various build issues on *BSD, Mac and Windows.
  Updated the configurations and the scripts for continuous integration.
  Cleaned up the code, the build scripts, and the documentation.
 Version 1.6.41 [January 24, 2024]
  Added SIMD-optimized code for the LoongArch LSX hardware.
    (Contributed by GuXiWei, JinBo and ZhangLixia)
  Fixed the run-time discovery of MIPS MSA hardware.
    (Contributed by Sui Jingfeng)
  Fixed an off-by-one error in the function png_do_check_palette_indexes(),
    which failed to recognize errors that might have existed in the first
    column of a broken palette-encoded image. This was a benign regression
    accidentally introduced in libpng-1.6.33. No pixel was harmed.
    (Contributed by Adam Richter; reviewed by John Bowler)
  Fixed, improved and modernized the contrib/pngminus programs, i.e.,
    png2pnm.c and pnm2png.c
  Removed old and peculiar portability hacks that were meant to silence
    warnings issued by gcc version 7.1 alone.
    (Contributed by John Bowler)
  Fixed and modernized the CMake file, and raised the minimum required
    CMake version from 3.1 to 3.6.
    (Contributed by Clinton Ingram, Timothy Lyanguzov, Tyler Kropp, et al.)
  Allowed the configure script to disable the building of auxiliary tools
    and tests, thus catching up with the CMake file.
    (Contributed by Carlo Bramini)
  Fixed a build issue on Mac.
    (Contributed by Zixu Wang)
  Moved the Autoconf macro files to scripts/autoconf.
  Moved the CMake files (except for the main CMakeLists.txt) to
    scripts/cmake and moved the list of their contributing authors to
    scripts/cmake/AUTHORS.md
  Updated the CI configurations and scripts.
  Relicensed the CI scripts to the MIT License.
  Improved the test coverage.
    (Contributed by John Bowler)
 Version 1.6.42 [January 29, 2024]
  Fixed the implementation of the macro function png_check_sig().
    This was an API regression, introduced in libpng-1.6.41.
    (Reported by Matthieu Darbois)
  Fixed and updated the libpng manual.
 Version 1.6.43 [February 23, 2024]
  Fixed the row width check in png_check_IHDR().
    This corrected a bug that was specific to the 16-bit platforms,
    and removed a spurious compiler warning from the 64-bit builds.
    (Reported by Jacek Caban; fixed by John Bowler)
  Added eXIf chunk support to the push-mode reader in pngpread.c.
    (Contributed by Chris Blume)
  Added contrib/pngexif for the benefit of the users who would like
    to inspect the content of eXIf chunks.
  Added contrib/conftest/basic.dfa, a basic build-time configuration.
    (Contributed by John Bowler)
  Fixed a preprocessor condition in pngread.c that broke build-time
    configurations like contrib/conftest/pngcp.dfa.
    (Contributed by John Bowler)
  Added CMake build support for LoongArch LSX.
    (Contributed by GuXiWei)
  Fixed a CMake build error that occurred under a peculiar state of the
    dependency tree. This was a regression introduced in libpng-1.6.41.
    (Contributed by Dan Rosser)
  Marked the installed libpng headers as system headers in CMake.
    (Contributed by Benjamin Buch)
  Updated the build support for RISCOS.
    (Contributed by Cameron Cawley)
  Updated the makefiles to allow cross-platform builds to initialize
    conventional make variables like AR and ARFLAGS.
  Added various improvements to the CI scripts in areas like version
    consistency verification and text linting.
  Added version consistency verification to pngtest.c also.
 Version 1.6.44 [September 12, 2024]
  Hardened calculations in chroma handling to prevent overflows, and
    relaxed a constraint in cHRM validation to accomodate the standard
    ACES AP1 set of color primaries.
    (Contributed by John Bowler)
  Removed the ASM implementation of ARM Neon optimizations and updated
    the build accordingly. Only the remaining C implementation shall be
    used from now on, thus ensuring the support of the PAC/BTI security
    features on ARM64.
    (Contributed by Ross Burton and John Bowler)
  Fixed the pickup of the PNG_HARDWARE_OPTIMIZATIONS option in the
    CMake build on FreeBSD/amd64. This is an important performance fix
    on this platform.
  Applied various fixes and improvements to the CMake build.
    (Contributed by Eric Riff, Benjamin Buch and Erik Scholz)
  Added fuzzing targets for the simplified read API.
    (Contributed by Mikhail Khachayants)
  Fixed a build error involving pngtest.c under a custom config.
    This was a regression introduced in a code cleanup in libpng-1.6.43.
    (Contributed by Ben Wagner)
  Fixed and improved the config files for AppVeyor CI and Travis CI.
 Version 1.6.45 [January 7, 2025]
  Added support for the cICP chunk.
    (Contributed by Lucas Chollet and John Bowler)
  Adjusted and improved various checks in colorspace calculations.
    (Contributed by John Bowler)
  Rearranged the write order of colorspace chunks for better conformance
    with the PNG v3 draft specification.
    (Contributed by John Bowler)
  Raised the minimum required CMake version from 3.6 to 3.14.
  Forked off a development branch for libpng version 1.8.
 Version 1.6.46 [January 23, 2025]
  Added support for the mDCV and cLLI chunks.
    (Contributed by John Bowler)
  Fixed a build issue affecting C89 compilers.
    This was a regression introduced in libpng-1.6.45.
    (Contributed by John Bowler)
  Added makefile.c89, specifically for testing C89 compilers.
  Cleaned up contrib/pngminus: corrected an old typo, removed an old
    workaround, and updated the CMake file.
 Version 1.6.47 [February 18, 2025]
  Modified the behaviour of colorspace chunks in order to adhere
    to the new precedence rules formulated in the latest draft of
    the PNG Specification.
    (Contributed by John Bowler)
  Fixed a latent bug in `png_write_iCCP`.
    This would have been a read-beyond-end-of-malloc vulnerability,
    introduced early in the libpng-1.6.0 development, yet (fortunately!)
    it was inaccessible before the above-mentioned modification of the
    colorspace precedence rules, due to pre-existing colorspace checks.
    (Reported by Bob Friesenhahn; fixed by John Bowler)
 Version 1.6.48 [April 30, 2025]
  Fixed the floating-point version of the mDCv setter `png_set_mDCv`.
    (Reported by Mohit Bakshi; fixed by John Bowler)
  Added #error directives to discourage the inclusion of private
    libpng implementation header files in PNG-supporting applications.
  Added the CMake build option `PNG_LIBCONF_HEADER`, to be used as an
    alternative to `DFA_XTRA`.
  Removed the Travis CI configuration files, with heartfelt thanks for
    their generous support of our project over the past five years!
 Version 1.6.49 [June 12, 2025]
  Added SIMD-optimized code for the RISC-V Vector Extension (RVV).
    (Contributed by Manfred Schlaegl, Dragos Tiselice and Filip Wasil)
  Added various fixes and improvements to the build scripts and to
    the sample code.
 Version 1.6.50 [July 1, 2025]
  Improved the detection of the RVV Extension on the RISC-V platform.
    (Contributed by Filip Wasil)
  Replaced inline ASM with C intrinsics in the RVV code.
    (Contributed by Filip Wasil)
  Fixed a decoder defect in which unknown chunks trailing IDAT, set
    to go through the unknown chunk handler, incorrectly triggered
    out-of-place IEND errors.
    (Contributed by John Bowler)
  Fixed the CMake file for cross-platform builds that require `libm`.
 Version 1.6.51 [TODO]
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net.
 Subscription is required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
--- a/98
+++ b/98
@ -1,3 +1,4 @@
    Installing libpng
 Contents
@ -127,18 +128,16 @@ Your directory structure should look like this:
          README
          *.h, *.c  => libpng source files
          CMakeLists.txt    =>  "cmake" script
          ci
             ci_*.sh
          configuration files:
             configure.ac, configure, Makefile.am, Makefile.in,
             autogen.sh, config.guess, ltmain.sh, missing, libpng.pc.in,
             libpng-config.in, aclocal.m4, config.h.in, config.sub,
-             depcomp, install-sh, mkinstalldirs, test-pngtest.sh, etc.
+             depcomp, install-sh, mkinstalldirs, test-pngtest.sh
          contrib
             arm-neon, conftest, examples, gregbook, libtests, pngminim,
-             pngminus, pngsuite, tools, visupng, riscv-rvv
+             pngminus, pngsuite, tools, visupng
          projects
-             owatcom, visualc71, vstudio
+             cbuilder5, owatcom, visualc71, vstudio, xcode
          scripts
             makefile.*
             *.def (module definition files)
@ -146,7 +145,7 @@ Your directory structure should look like this:
          pngtest.png
          etc.
      zlib
-          README, *.h, *.c, contrib, etc.
+          README, *.h, *.c contrib, etc.
 If the line endings in the files look funny, you may wish to get the other
 distribution of libpng.  It is available in both tar.gz (UNIX style line
@ -154,27 +153,28 @@ endings) and zip (DOS style line endings) formats.
 VI. Building with project files
-If you are building libpng with Microsoft Visual Studio, you can enter
+If you are building libpng with MSVC, you can enter the
-the directory projects\visualc71 or projects\vstudio and follow the
+libpng projects\visualc71 or vstudio directory and follow the instructions
-instructions in README.txt.
+in README.txt.
-Otherwise, enter the zlib directory and follow the instructions in
+Otherwise enter the zlib directory and follow the instructions in zlib/README,
-zlib/README, then come back here and run "configure" or choose the
+then come back here and run "configure" or choose the appropriate
-appropriate makefile in the scripts directory.
+makefile.sys in the scripts directory.
 VII. Building with makefiles
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example
 MSDOS example:
    copy scripts\makefile.msc makefile
    copy scripts\pnglibconf.h.prebuilt pnglibconf.h
 UNIX example:
-    cp scripts/makefile.std Makefile
+    cp scripts/makefile.std makefile
-    make
+    cp scripts/pnglibconf.h.prebuilt pnglibconf.h
 Windows example:
    nmake -f scripts\makefile.vcwin32
 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
@ -191,33 +191,36 @@ test.  For more confidence, you can run another test by typing
 Also, you can run "pngtest -m contrib/pngsuite/*.png" and compare
 your output with the result shown in contrib/pngsuite/README.
-Most of the makefiles used to allow you to run "make install" to put
+Most of the makefiles will allow you to run "make install" to
-the library in its final resting place, but that feature is no longer
+put the library in its final resting place (if you want to
-supported.  The only tested and supported manners to install libpng are
+do that, run "make install" in the zlib directory first if necessary).
-the conventional build and install procedures driven by the configure
+Some also allow you to run "make test-installed" after you have
-script or by the CMake file.
+run "make install".
-VIII. Configuring for DOS and other 16-bit platforms
+VIII. Configuring libpng for 16-bit platforms
-Officially, the support for 16-bit platforms has been removed.
+You will want to look into zconf.h to tell zlib (and thus libpng) that
 it cannot allocate more than 64K at a time.  Even if you can, the memory
 won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
 IX. Configuring for DOS
 For DOS users who only have access to the lower 640K, you will
 have to limit zlib's memory usage via a png_set_compression_mem_level()
 call.  See zlib.h or zconf.h in the zlib library for more information.
-You may be or may not be in luck if you target the "large" memory model,
+X. Configuring for Medium Model
 but all the smaller models ("small", "compact" and "medium") are known
 to be unworkable.  For DOS users who have access beyond the lower 640K,
 a "flat" 32-bit DOS model (such as DJGPP) is strongly recommended.
-For DOS users who only have access to the lower 640K, you will have to
+Libpng's support for medium model has been tested on most of the popular
-limit zlib's memory usage via a png_set_compression_mem_level() call.
+compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
-You will also have to look into zconf.h to tell zlib (and thus libpng)
+defined, and FAR gets defined to far in pngconf.h, and you should be
-that it cannot allocate more than 64K at a time.  Even if you can, the
+all set.  Everything in the library (except for zlib's structure) is
-memory won't be accessible.  Therefore, you should limit zlib and libpng
+expecting far data.  You must use the typedefs with the p or pp on
-to 64K by defining MAXSEG_64K.
+the end for pointers (or at least look at them and be careful).  Make
 note that the rows of data are defined as png_bytepp, which is
 an "unsigned char far * far *".
-IX. Prepending a prefix to exported symbols
+XI. Prepending a prefix to exported symbols
 Starting with libpng-1.6.0, you can configure libpng (when using the
 "configure" script) to prefix all exported symbols by means of the
@ -228,7 +231,7 @@ identifier).  This creates a set of macros in pnglibconf.h, so this is
 transparent to applications; their function calls get transformed by
 the macros to use the modified names.
-X. Configuring for compiler xxx:
+XII. Configuring for compiler xxx:
 All includes for libpng are in pngconf.h.  If you need to add, change
 or delete an include, this is the place to do it.
@ -240,7 +243,7 @@ As of libpng-1.5.0, pngpriv.h also includes three other private header
 files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
 that previously appeared in the public headers.
-XI. Removing unwanted object code
+XIII. Removing unwanted object code
 There are a bunch of #define's in pngconf.h that control what parts of
 libpng are compiled.  All the defines end in _SUPPORTED.  If you are
@ -279,7 +282,7 @@ library to fail if they call functions not available in your library.
 The size of the library itself should not be an issue, because only
 those sections that are actually used will be loaded into memory.
-XII. Enabling or disabling hardware optimizations
+XIV. Enabling or disabling hardware optimizations
 Certain hardware capabilities, such as the Intel SSE instructions,
 are normally detected at run time. Enable them with configure options
@ -289,7 +292,6 @@ such as one of
   --enable-mips-msa=yes
   --enable-intel-sse=yes
   --enable-powerpc-vsx=yes
   --enable-riscv-rvv=yes
 or enable them all at once with
@ -302,7 +304,6 @@ or more of
   CPPFLAGS += "-DPNG_MIPS_MSA"
   CPPFLAGS += "-DPNG_INTEL_SSE"
   CPPFLAGS += "-DPNG_POWERPC_VSX"
   CPPFLAGS += "-DPNG_RISCV_RVV"
 See for example scripts/makefile.linux-opt
@ -319,21 +320,19 @@ to disable a particular one,
 or via compiler-command options such as
   CPPFLAGS += "-DPNG_ARM_NEON_OPT=0, -DPNG_MIPS_MSA_OPT=0,
-   -DPNG_INTEL_SSE_OPT=0, -DPNG_POWERPC_VSX_OPT=0,
+   -DPNG_INTEL_SSE_OPT=0, -DPNG_POWERPC_VSX_OPT=0"
   -DPNG_RISCV_RVV_OPT=0"
 If you are using cmake, hardware optimizations are "on"
 by default. To disable them, use
    cmake . -DPNG_ARM_NEON=no -DPNG_INTEL_SSE=no \
-            -DPNG_MIPS_MSA=no -DPNG_POWERPC_VSX=no \
+            -DPNG_MIPS_MSA=no -DPNG_POWERPC_VSX=no
            -DPNG_RISCV_RVV=no
 or disable them all at once with
    cmake . -DPNG_HARDWARE_OPTIMIZATIONS=no
-XIII. Changes to the build and configuration of libpng in libpng-1.5.x
+XV. Changes to the build and configuration of libpng in libpng-1.5.x
 Details of internal changes to the library code can be found in the CHANGES
 file and in the GIT repository logs.  These will be of no concern to the vast
@ -424,7 +423,7 @@ $PREFIX/include directory).  Do not edit pnglibconf.h after you have built
 libpng, because than the settings would not accurately reflect the settings
 that were used to build libpng.
-XIV. Setjmp/longjmp issues
+XVI. Setjmp/longjmp issues
 Libpng uses setjmp()/longjmp() for error handling.  Unfortunately setjmp()
 is known to be not thread-safe on some platforms and we don't know of
@ -442,7 +441,7 @@ This requires setjmp/longjmp, so you must either build the library
 with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
 and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
-XV. Common linking failures
+XVII. Common linking failures
 If your application fails to find libpng or zlib entries while linking:
@ -454,13 +453,12 @@ If your application fails to find libpng or zlib entries while linking:
  If you are using the vstudio project, observe the WARNING in
  project/vstudio/README.txt.
-XVI. Other sources of information about libpng:
+XVIII. Other sources of information about libpng:
 Further information can be found in the README and libpng-manual.txt
 files, in the individual makefiles, in png.h, and the manual pages
 libpng.3 and png.5.
 Copyright (c) 2022 Cosmin Truta
 Copyright (c) 1998-2002,2006-2016 Glenn Randers-Pehrson
 This document is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
--- a/4
+++ b/4
@ -4,8 +4,8 @@ COPYRIGHT NOTICE, DISCLAIMER, and LICENSE
 PNG Reference Library License version 2
 ---------------------------------------
- * Copyright (c) 1995-2025 The PNG Reference Library Authors.
+ * Copyright (c) 1995-2019 The PNG Reference Library Authors.
- * Copyright (c) 2018-2025 Cosmin Truta.
+ * Copyright (c) 2018-2019 Cosmin Truta.
 * Copyright (c) 2000-2002, 2004, 2006-2018 Glenn Randers-Pehrson.
 * Copyright (c) 1996-1997 Andreas Dilger.
 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
--- a/Makefile.am
+++ b/Makefile.am
@ -1,6 +1,6 @@
 # Makefile.am, the source file for Makefile.in (and hence Makefile), is
 #
-# Copyright (c) 2018-2025 Cosmin Truta
+# Copyright (c) 2018 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
@ -9,24 +9,16 @@
 PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
-ACLOCAL_AMFLAGS = -I scripts/autoconf
+ACLOCAL_AMFLAGS = -I scripts
 # test programs - run on make check, make distcheck
 if ENABLE_TESTS
 check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage pngcp
 if HAVE_CLOCK_GETTIME
 check_PROGRAMS += timepng
 endif
 else
 check_PROGRAMS=
 endif
 # Utilities - installed
 if ENABLE_TOOLS
 bin_PROGRAMS= pngfix png-fix-itxt
 else
 bin_PROGRAMS=
 endif
 # This ensures that pnglibconf.h gets built at the start of 'make all' or
 # 'make check', but it does not add dependencies to the individual programs,
@ -38,7 +30,6 @@ endif
 # always wrong and always very confusing.
 BUILT_SOURCES = pnglibconf.h
 if ENABLE_TESTS
 pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
@ -57,22 +48,19 @@ pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 timepng_SOURCES = contrib/libtests/timepng.c
 timepng_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngcp_SOURCES = contrib/tools/pngcp.c
 pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 endif
 if ENABLE_TOOLS
 pngfix_SOURCES = contrib/tools/pngfix.c
 pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
-endif
+
 pngcp_SOURCES = contrib/tools/pngcp.c
 pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 if ENABLE_TESTS
 TESTS =\
-   tests/pngtest-all\
+   tests/pngtest\
   tests/pngtest-badpngs\
   tests/pngvalid-gamma-16-to-8 tests/pngvalid-gamma-alpha-mode\
   tests/pngvalid-gamma-background tests/pngvalid-gamma-expand16-alpha-mode\
   tests/pngvalid-gamma-expand16-background\
@ -88,7 +76,6 @@ TESTS =\
   tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
   tests/pngimage-quick tests/pngimage-full
 endif
 # man pages
 dist_man_MANS= libpng.3 libpngpf.3 png.5
@ -108,7 +95,7 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
 if PNG_ARM_NEON
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
-	arm/filter_neon_intrinsics.c \
+	arm/filter_neon.S arm/filter_neon_intrinsics.c \
 	arm/palette_neon_intrinsics.c
 endif
@ -117,13 +104,6 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/mips_init.c\
 	mips/filter_msa_intrinsics.c
 endif
 if PNG_MIPS_MMI
 if !PNG_MIPS_MSA
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/mips_init.c
 endif
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += mips/filter_mmi_inline_assembly.c
 endif
 if PNG_INTEL_SSE
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += intel/intel_init.c\
 	intel/filter_sse2_intrinsics.c
@ -134,22 +114,6 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += powerpc/powerpc_init.c\
        powerpc/filter_vsx_intrinsics.c
 endif
 if PNG_RISCV_RVV
 noinst_LTLIBRARIES= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@rvv.la
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@rvv_la_SOURCES = riscv/riscv_init.c\
        riscv/filter_rvv_intrinsics.c
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@rvv_la_CFLAGS = -march=rv64gv
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@rvv.la
 endif
 if PNG_LOONGARCH_LSX
 noinst_LTLIBRARIES= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_SOURCES = loongarch/loongarch_lsx_init.c\
 	loongarch/filter_lsx_intrinsics.c
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx_la_CFLAGS = -mlsx
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LIBADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
 endif
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_LDFLAGS = -no-undefined -export-dynamic \
@ -170,14 +134,6 @@ else
  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES = libpng.sym
 endif
 if PNG_RISCV_RVV
  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES += libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@rvv.la
 endif
 if PNG_LOONGARCH_LSX
  libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_DEPENDENCIES += libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@lsx.la
 endif
 #distribute headers in /usr/include/libpng/*
 pkgincludedir= $(includedir)/$(PNGLIB_BASENAME)
 pkginclude_HEADERS= png.h pngconf.h
@ -194,7 +150,7 @@ pkgconfig_DATA = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc
 EXTRA_DIST= \
 	ANNOUNCE AUTHORS CHANGES INSTALL LICENSE README TODO TRADEMARK \
 	pngtest.png pngbar.png pngnow.png pngbar.jpg autogen.sh \
-	${srcdir}/ci ${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
+	${srcdir}/contrib ${srcdir}/projects ${srcdir}/scripts \
 	$(TESTS) $(XFAIL_TESTS) tests/pngstest \
 	CMakeLists.txt example.c libpng-manual.txt
@ -210,7 +166,7 @@ MAINTAINERCLEANFILES = Makefile.in aclocal.m4 config.guess config.h.in \
 config.sub configure depcomp install-sh ltmain.sh missing
 # PNG_COPTS give extra options for the C compiler to be used on all compilation
-# steps (unless target_CFLAGS is specified; that will take precedence over
+# steps (unless targe_CFLAGS is specified; that will take precedence over
 # AM_CFLAGS)
 PNG_COPTS = @PNG_COPTS@
 AM_CFLAGS = ${PNG_COPTS}
--- a/Makefile.in
+++ b/Makefile.in
--- a/299
+++ b/299
@ -1,88 +1,57 @@
-README for libpng version 1.6.51.git
+README for libpng version 1.6.37 - April 14, 2019
-====================================
+=================================================
-See the note about version numbers near the top of `png.h`.
+See the note about version numbers near the top of png.h.
-See `INSTALL` for instructions on how to install libpng.
+See INSTALL for instructions on how to install libpng.
-Libpng comes in several distribution formats.  Get `libpng-*.tar.gz`
+Libpng comes in several distribution formats.  Get libpng-*.tar.gz or
-or `libpng-*.tar.xz` if you want UNIX-style line endings in the text
+libpng-*.tar.xz or if you want UNIX-style line endings in the text
-files, or `lpng*.7z` or `lpng*.zip` if you want DOS-style line endings.
+files, or lpng*.7z or lpng*.zip if you want DOS-style line endings.
-For a detailed description on using libpng, read `libpng-manual.txt`.
+Version 0.89 was the first official release of libpng.  Don't let the
-For examples of libpng in a program, see `example.c` and `pngtest.c`.
+fact that it's the first release fool you.  The libpng library has been
-For usage information and restrictions (what little they are) on libpng,
+in extensive use and testing since mid-1995.  By late 1997 it had
-see `png.h`.  For a description on using zlib (the compression library
+finally gotten to the stage where there hadn't been significant
-used by libpng) and zlib's restrictions, see `zlib.h`.
+changes to the API in some time, and people have a bad feeling about
 libraries with versions < 1.0.  Version 1.0.0 was released in
 March 1998.
-You should use zlib 1.0.4 or later to run this, but it _may_ work with
+****
-versions as old as zlib 0.95.  Even so, there are bugs in older zlib
+Note that some of the changes to the png_info structure render this
 versions which can cause the output of invalid compression streams for
 some images.
 You should also note that zlib is a compression library that is useful
 for more things than just PNG files.  You can use zlib as a drop-in
 replacement for `fread()` and `fwrite()`, if you are so inclined.
 zlib should be available at the same place that libpng is, or at
 https://zlib.net .
 You may also want a copy of the PNG specification.  It is available
 as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
 these at http://www.libpng.org/pub/png/pngdocs.html .
 This code is currently being archived at https://libpng.sourceforge.io
 in the download area, and at http://libpng.download/src .
 This release, based in a large way on Glenn's, Guy's and Andreas'
 earlier work, was created and will be supported by myself and the PNG
 development group.
 Send comments, corrections and commendations to `png-mng-implement`
 at `lists.sourceforge.net`.  (Subscription is required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
 to subscribe.)
 Send general questions about the PNG specification to `png-mng-misc`
 at `lists.sourceforge.net`.  (Subscription is required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-misc
 to subscribe.)
 Historical notes
 ----------------
 The libpng library has been in extensive use and testing since mid-1995.
 Version 0.89, published a year later, was the first official release.
 By late 1997, it had finally gotten to the stage where there hadn't
 been significant changes to the API in some time, and people have a bad
 feeling about libraries with versions below 1.0.  Version 1.0.0 was
 released in March 1998.
 Note that some of the changes to the `png_info` structure render this
 version of the library binary incompatible with libpng-0.89 or
 earlier versions if you are using a shared library.  The type of the
-`filler` parameter for `png_set_filler()` has changed from `png_byte`
+"filler" parameter for png_set_filler() has changed from png_byte to
-to `png_uint_32`, which will affect shared-library applications that
+png_uint_32, which will affect shared-library applications that use
-use this function.
+this function.
-To avoid problems with changes to the internals of the `info_struct`,
+To avoid problems with changes to the internals of the png info_struct,
 new APIs have been made available in 0.95 to avoid direct application
-access to `info_ptr`.  These functions are the `png_set_<chunk>` and
+access to info_ptr.  These functions are the png_set_<chunk> and
-`png_get_<chunk>` functions.  These functions should be used when
+png_get_<chunk> functions.  These functions should be used when
-accessing/storing the `info_struct` data, rather than manipulating it
+accessing/storing the info_struct data, rather than manipulating it
 directly, to avoid such problems in the future.
 It is important to note that the APIs did not make current programs
 that access the info struct directly incompatible with the new
 library, through libpng-1.2.x.  In libpng-1.4.x, which was meant to
-be a transitional release, members of the `png_struct` and the
+be a transitional release, members of the png_struct and the
-`info_struct` can still be accessed, but the compiler will issue a
+info_struct can still be accessed, but the compiler will issue a
 warning about deprecated usage.  Since libpng-1.5.0, direct access
 to these structs is not allowed, and the definitions of the structs
-reside in private `pngstruct.h` and `pnginfo.h` header files that are
+reside in private pngstruct.h and pnginfo.h header files that are not
-not accessible to applications.  It is strongly suggested that new
+accessible to applications.  It is strongly suggested that new
-programs use the new APIs (as shown in `example.c` and `pngtest.c`),
+programs use the new APIs (as shown in example.c and pngtest.c), and
-and older programs be converted to the new format, to facilitate
+older programs be converted to the new format, to facilitate upgrades
-upgrades in the future.
+in the future.
 ****
 Additions since 0.90 include the ability to compile libpng as a
 Windows DLL, and new APIs for accessing data in the info struct.
 Experimental functions include the ability to set weighting and cost
 factors for row filter selection, direct reads of integers from buffers
 on big-endian processors that support misaligned data access, faster
 methods of doing alpha composition, and more accurate 16->8 bit color
 conversion.
 The additions since 0.89 include the ability to read from a PNG stream
 which has had some (or all) of the signature bytes read by the calling
@ -92,88 +61,118 @@ the library action on the detection of chunk CRC errors.  It is possible
 to set different actions based on whether the CRC error occurred in a
 critical or an ancillary chunk.
-The additions since 0.90 include the ability to compile libpng as a
+For a detailed description on using libpng, read libpng-manual.txt.
-Windows DLL, and new APIs for accessing data in the `info_struct`.
+For examples of libpng in a program, see example.c and pngtest.c.  For
-Experimental functions included the ability to set weighting and cost
+usage information and restrictions (what little they are) on libpng,
-factors for row filter selection, direct reads of integers from buffers
+see png.h.  For a description on using zlib (the compression library
-on big-endian processors that support misaligned data access, faster
+used by libpng) and zlib's restrictions, see zlib.h
 methods of doing alpha composition, and more accurate 16-to-8 bit color
 conversion.  Some of these experimental functions, such as the weighted
 filter heuristics, have since been removed.
-Files included in this distribution
+I have included a general makefile, as well as several machine and
-----------------------------------
+compiler specific ones, but you may have to modify one for your own
 needs.
-    ANNOUNCE      =>  Announcement of this version, with recent changes
+You should use zlib 1.0.4 or later to run this, but it MAY work with
-    AUTHORS       =>  List of contributing authors
+versions as old as zlib 0.95.  Even so, there are bugs in older zlib
-    CHANGES       =>  Description of changes between libpng versions
+versions which can cause the output of invalid compression streams for
-    INSTALL       =>  Instructions to install libpng
+some images.
-    LICENSE       =>  License to use and redistribute libpng
+
-    README        =>  This file
+You should also note that zlib is a compression library that is useful
-    TODO          =>  Things not implemented in the current library
+for more things than just PNG files.  You can use zlib as a drop-in
-    TRADEMARK     =>  Trademark information
+replacement for fread() and fwrite(), if you are so inclined.
-    example.c     =>  Example code for using libpng functions
+
-    libpng.3      =>  Manual page for libpng (includes libpng-manual.txt)
+zlib should be available at the same place that libpng is, or at
-    libpng-manual.txt  =>  Description of libpng and its functions
+https://zlib.net.
-    libpngpf.3    =>  Manual page for libpng's private functions (deprecated)
+
-    png.5         =>  Manual page for the PNG format
+You may also want a copy of the PNG specification.  It is available
-    png.c         =>  Basic interface functions common to library
+as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
-    png.h         =>  Library function and interface declarations (public)
+these at http://www.libpng.org/pub/png/pngdocs.html .
-    pngpriv.h     =>  Library function and interface declarations (private)
+
-    pngconf.h     =>  System specific library configuration (public)
+This code is currently being archived at libpng.sourceforge.io in the
-    pngstruct.h   =>  png_struct declaration (private)
+[DOWNLOAD] area, and at http://libpng.download/src .
-    pnginfo.h     =>  png_info struct declaration (private)
+
-    pngdebug.h    =>  debugging macros (private)
+This release, based in a large way on Glenn's, Guy's and Andreas'
-    pngerror.c    =>  Error/warning message I/O functions
+earlier work, was created and will be supported by myself and the PNG
-    pngget.c      =>  Functions for retrieving info from struct
+development group.
-    pngmem.c      =>  Memory handling functions
+
-    pngbar.png    =>  PNG logo, 88x31
+Send comments/corrections/commendations to png-mng-implement at
-    pngnow.png    =>  PNG logo, 98x31
+lists.sourceforge.net (subscription required; visit
-    pngpread.c    =>  Progressive reading functions
+https://lists.sourceforge.net/lists/listinfo/png-mng-implement
-    pngread.c     =>  Read data/helper high-level functions
+to subscribe).
-    pngrio.c      =>  Lowest-level data read I/O functions
+
-    pngrtran.c    =>  Read data transformation functions
+Send general questions about the PNG specification to png-mng-misc
-    pngrutil.c    =>  Read data utility functions
+at lists.sourceforge.net (subscription required; visit
-    pngset.c      =>  Functions for storing data into the info_struct
+https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
-    pngtest.c     =>  Library test program
+subscribe).
-    pngtest.png   =>  Library test sample image
+
-    pngtrans.c    =>  Common data transformation functions
+Files in this distribution:
-    pngwio.c      =>  Lowest-level write I/O functions
+
-    pngwrite.c    =>  High-level write functions
+      ANNOUNCE      =>  Announcement of this version, with recent changes
-    pngwtran.c    =>  Write data transformations
+      AUTHORS       =>  List of contributing authors
-    pngwutil.c    =>  Write utility functions
+      CHANGES       =>  Description of changes between libpng versions
-    arm/          =>  Optimized code for ARM Neon
+      KNOWNBUG      =>  List of known bugs and deficiencies
-    intel/        =>  Optimized code for INTEL SSE2
+      LICENSE       =>  License to use and redistribute libpng
-    loongarch/    =>  Optimized code for LoongArch LSX
+      README        =>  This file
-    mips/         =>  Optimized code for MIPS MSA and MIPS MMI
+      TODO          =>  Things not implemented in the current library
-    powerpc/      =>  Optimized code for PowerPC VSX
+      TRADEMARK     =>  Trademark information
-    riscv/        =>  Optimized code for the RISC-V platform
+      example.c     =>  Example code for using libpng functions
-    ci/           =>  Scripts for continuous integration
+      libpng.3      =>  manual page for libpng (includes libpng-manual.txt)
-    contrib/      =>  External contributions
+      libpng-manual.txt  =>  Description of libpng and its functions
-        arm-neon/     =>  Optimized code for the ARM-NEON platform
+      libpngpf.3    =>  manual page for libpng's private functions
-        mips-msa/     =>  Optimized code for the MIPS-MSA platform
+      png.5         =>  manual page for the PNG format
-        powerpc-vsx/  =>  Optimized code for the POWERPC-VSX platform
+      png.c         =>  Basic interface functions common to library
-        examples/     =>  Examples of libpng usage
+      png.h         =>  Library function and interface declarations (public)
-        gregbook/     =>  Source code for PNG reading and writing, from
+      pngpriv.h     =>  Library function and interface declarations (private)
-                          "PNG: The Definitive Guide" by Greg Roelofs,
+      pngconf.h     =>  System specific library configuration (public)
-                          O'Reilly, 1999
+      pngstruct.h   =>  png_struct declaration (private)
-        libtests/     =>  Test programs
+      pnginfo.h     =>  png_info struct declaration (private)
-        pngexif/      =>  Program to inspect the EXIF information in PNG files
+      pngdebug.h    =>  debugging macros (private)
-        pngminim/     =>  Minimal decoder, encoder, and progressive decoder
+      pngerror.c    =>  Error/warning message I/O functions
-                          programs demonstrating the use of pngusr.dfa
+      pngget.c      =>  Functions for retrieving info from struct
-        pngminus/     =>  Simple pnm2png and png2pnm programs
+      pngmem.c      =>  Memory handling functions
-        pngsuite/     =>  Test images
+      pngbar.png    =>  PNG logo, 88x31
-        riscv-rvv/    =>  Optimized code for the RISC-V Vector platform
+      pngnow.png    =>  PNG logo, 98x31
-        testpngs/     =>  Test images
+      pngpread.c    =>  Progressive reading functions
-        tools/        =>  Various tools
+      pngread.c     =>  Read data/helper high-level functions
-        visupng/      =>  VisualPng, a Windows viewer for PNG images
+      pngrio.c      =>  Lowest-level data read I/O functions
-    projects/     =>  Project files and workspaces for various IDEs
+      pngrtran.c    =>  Read data transformation functions
-        owatcom/      =>  OpenWatcom project
+      pngrutil.c    =>  Read data utility functions
-        visualc71/    =>  Microsoft Visual C++ 7.1 workspace
+      pngset.c      =>  Functions for storing data into the info_struct
-        vstudio/      =>  Microsoft Visual Studio workspace
+      pngtest.c     =>  Library test program
-    scripts/      =>  Scripts and makefiles for building libpng
+      pngtest.png   =>  Library test sample image
-                      (see scripts/README.txt for the complete list)
+      pngtrans.c    =>  Common data transformation functions
-    tests/        =>  Test scripts
+      pngwio.c      =>  Lowest-level write I/O functions
      pngwrite.c    =>  High-level write functions
      pngwtran.c    =>  Write data transformations
      pngwutil.c    =>  Write utility functions
      arm           =>  Contains optimized code for the ARM platform
      powerpc       =>  Contains optimized code for the PowerPC platform
      contrib       =>  Contributions
       arm-neon         =>  Optimized code for ARM-NEON platform
       powerpc-vsx      =>  Optimized code for POWERPC-VSX platform
       examples         =>  Example programs
       gregbook         =>  source code for PNG reading and writing, from
                            Greg Roelofs' "PNG: The Definitive Guide",
                            O'Reilly, 1999
       libtests         =>  Test programs
       mips-msa         =>  Optimized code for MIPS-MSA platform
       pngminim         =>  Minimal decoder, encoder, and progressive decoder
                            programs demonstrating use of pngusr.dfa
       pngminus         =>  Simple pnm2png and png2pnm programs
       pngsuite         =>  Test images
       testpngs
       tools            =>  Various tools
       visupng          =>  Contains a MSVC workspace for VisualPng
      intel             =>  Optimized code for INTEL-SSE2 platform
      mips              =>  Optimized code for MIPS platform
      projects      =>  Contains project files and workspaces for
                        building a DLL
       owatcom          =>  Contains a WATCOM project for building libpng
       visualc71        =>  Contains a Microsoft Visual C++ (MSVC)
                            workspace for building libpng and zlib
       vstudio          =>  Contains a Microsoft Visual C++ (MSVC)
                            workspace for building libpng and zlib
      scripts       =>  Directory containing scripts for building libpng:
                            (see scripts/README.txt for the list of scripts)
 Good luck, and happy coding!
--- a/43
+++ b/43
@ -1,22 +1,23 @@
-TODO list for libpng
+TODO - list of things to do for libpng:
 --------------------
- * Fix all defects (duh!)
+* Fix all defects (duh!)
- * cHRM transformation.
+* Better C++ wrapper / full C++ implementation (?)
- * Palette creation.
+* Fix the problems with C++ and 'extern "C"'.
- * "grayscale->palette" transformation and "palette->grayscale" detection.
+* cHRM transformation.
- * Improved dithering.
+* Palette creation.
- * Multi-lingual error and warning message support.
+* "grayscale->palette" transformation and "palette->grayscale" detection.
- * Complete sRGB transformation.  (Currently it simply uses gamma=0.45455.)
+* Improved dithering.
- * Man pages for function calls.
+* Multi-lingual error and warning message support.
- * Better documentation.
+* Complete sRGB transformation.  (Currently it simply uses gamma=0.45455.)
- * Better filter selection
+* Man pages for function calls.
-   (e.g., counting huffman bits/precompression; filter inertia; filter costs).
+* Better documentation.
- * Histogram creation.
+* Better filter selection
- * Text conversion between different code pages (e.g., Latin-1 to Mac).
+  (e.g., counting huffman bits/precompression; filter inertia; filter costs).
- * Avoid building gamma tables whenever possible.
+* Histogram creation.
- * Greater precision in changing to linear gamma for compositing against
+* Text conversion between different code pages (e.g., Latin-1 -> Mac).
-   background, and in doing rgb-to-gray transformations.
+* Avoid building gamma tables whenever possible.
- * Investigate pre-incremented loop counters and other loop constructions.
+* Greater precision in changing to linear gamma for compositing against
- * Interpolated method of handling interlacing.
+  background, and in doing rgb-to-gray transformations.
- * More validations for libpng transformations.
+* Investigate pre-incremented loop counters and other loop constructions.
 * Interpolated method of handling interlacing.
 * More validations for libpng transformations.
--- a/aclocal.m4
+++ b/aclocal.m4
@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.18.1 -*- Autoconf -*-
+# generated automatically by aclocal 1.16.1 -*- Autoconf -*-
-# Copyright (C) 1996-2025 Free Software Foundation, Inc.
+# Copyright (C) 1996-2018 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -14,13 +14,13 @@
 m4_ifndef([AC_CONFIG_MACRO_DIRS], [m4_defun([_AM_CONFIG_MACRO_DIRS], [])m4_defun([AC_CONFIG_MACRO_DIRS], [_AM_CONFIG_MACRO_DIRS($@)])])
 m4_ifndef([AC_AUTOCONF_VERSION],
  [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
-m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.72],,
+m4_if(m4_defn([AC_AUTOCONF_VERSION]), [2.69],,
-[m4_warning([this file was generated for autoconf 2.72.
+[m4_warning([this file was generated for autoconf 2.69.
 You have another version of autoconf.  It may work, but is not guaranteed to.
 If you have problems, you may need to regenerate the build system entirely.
 To do so, use the procedure documented by the package, typically 'autoreconf'.])])
-# Copyright (C) 2002-2025 Free Software Foundation, Inc.
+# Copyright (C) 2002-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -32,10 +32,10 @@ To do so, use the procedure documented by the package, typically 'autoreconf'.])
 # generated from the m4 files accompanying Automake X.Y.
 # (This private macro should not be called outside this file.)
 AC_DEFUN([AM_AUTOMAKE_VERSION],
-[am__api_version='1.18'
+[am__api_version='1.16'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.18.1], [],
+m4_if([$1], [1.16.1], [],
      [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
@ -51,14 +51,14 @@ m4_define([_AM_AUTOCONF_VERSION], [])
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 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.18.1])dnl
+[AM_AUTOMAKE_VERSION([1.16.1])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
  [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 # Figure out how to run the assembler.                      -*- Autoconf -*-
-# Copyright (C) 2001-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -78,7 +78,7 @@ _AM_IF_OPTION([no-dependencies],, [_AM_DEPENDENCIES([CCAS])])dnl
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
-# Copyright (C) 2001-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -130,7 +130,7 @@ am_aux_dir=`cd "$ac_aux_dir" && pwd`
 # AM_CONDITIONAL                                            -*- Autoconf -*-
-# Copyright (C) 1997-2025 Free Software Foundation, Inc.
+# Copyright (C) 1997-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -161,7 +161,7 @@ AC_CONFIG_COMMANDS_PRE(
 Usually this means the macro was only invoked conditionally.]])
 fi])])
-# Copyright (C) 1999-2025 Free Software Foundation, Inc.
+# Copyright (C) 1999-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -293,7 +293,7 @@ AC_CACHE_CHECK([dependency style of $depcc],
      # icc doesn't choke on unknown options, it will just issue warnings
      # or remarks (even with -Werror).  So we grep stderr for any message
      # that says an option was ignored or not supported.
-      # When given -MP, icc 7.0 and 7.1 complain thus:
+      # When given -MP, icc 7.0 and 7.1 complain thusly:
      #   icc: Command line warning: ignoring option '-M'; no argument required
      # The diagnosis changed in icc 8.0:
      #   icc: Command line remark: option '-MP' not supported
@ -352,7 +352,7 @@ _AM_SUBST_NOTMAKE([am__nodep])dnl
 # Generate code to set up dependency tracking.              -*- Autoconf -*-
-# Copyright (C) 1999-2025 Free Software Foundation, Inc.
+# Copyright (C) 1999-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -391,9 +391,7 @@ AC_DEFUN([_AM_OUTPUT_DEPENDENCY_COMMANDS],
  done
  if test $am_rc -ne 0; then
    AC_MSG_FAILURE([Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  If GNU make was not used, consider
+    for automatic dependency tracking.  Try re-running configure with the
    re-running the configure script with MAKE="gmake" (or whatever is
    necessary).  You can also try re-running configure with the
    '--disable-dependency-tracking' option to at least be able to build
    the package (albeit without support for automatic dependency tracking).])
  fi
@ -420,7 +418,7 @@ AC_DEFUN([AM_OUTPUT_DEPENDENCY_COMMANDS],
 # Do all the work for Automake.                             -*- Autoconf -*-
-# Copyright (C) 1996-2025 Free Software Foundation, Inc.
+# Copyright (C) 1996-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -448,10 +446,6 @@ m4_defn([AC_PROG_CC])
 # release and drop the old call support.
 AC_DEFUN([AM_INIT_AUTOMAKE],
 [AC_PREREQ([2.65])dnl
 m4_ifdef([_$0_ALREADY_INIT],
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 dnl Autoconf wants to disallow AM_ names.  We explicitly allow
 dnl the ones we care about.
 m4_pattern_allow([^AM_[A-Z]+FLAGS$])dnl
@ -488,7 +482,7 @@ m4_ifval([$3], [_AM_SET_OPTION([no-define])])dnl
 [_AM_SET_OPTIONS([$1])dnl
 dnl Diagnose old-style AC_INIT with new-style AM_AUTOMAKE_INIT.
 m4_if(
-  m4_ifset([AC_PACKAGE_NAME], [ok]):m4_ifset([AC_PACKAGE_VERSION], [ok]),
+  m4_ifdef([AC_PACKAGE_NAME], [ok]):m4_ifdef([AC_PACKAGE_VERSION], [ok]),
  [ok:ok],,
  [m4_fatal([AC_INIT should be called with package and version arguments])])dnl
 AC_SUBST([PACKAGE], ['AC_PACKAGE_TARNAME'])dnl
@ -520,9 +514,8 @@ AC_REQUIRE([AC_PROG_AWK])dnl
 AC_REQUIRE([AC_PROG_MAKE_SET])dnl
 AC_REQUIRE([AM_SET_LEADING_DOT])dnl
 _AM_IF_OPTION([tar-ustar], [_AM_PROG_TAR([ustar])],
-  [_AM_IF_OPTION([tar-pax], [_AM_PROG_TAR([pax])],
+	      [_AM_IF_OPTION([tar-pax], [_AM_PROG_TAR([pax])],
-    [_AM_IF_OPTION([tar-v7], [_AM_PROG_TAR([v7])],
+			     [_AM_PROG_TAR([v7])])])
      [_AM_PROG_TAR([ustar])])])])
 _AM_IF_OPTION([no-dependencies],,
 [AC_PROVIDE_IFELSE([AC_PROG_CC],
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@ -541,21 +534,7 @@ AC_PROVIDE_IFELSE([AC_PROG_OBJCXX],
 		  [m4_define([AC_PROG_OBJCXX],
 			     m4_defn([AC_PROG_OBJCXX])[_AM_DEPENDENCIES([OBJCXX])])])dnl
 ])
-# Variables for tags utilities; see am/tags.am
+AC_REQUIRE([AM_SILENT_RULES])dnl
 if test -z "$CTAGS"; then
  CTAGS=ctags
 fi
 AC_SUBST([CTAGS])
 if test -z "$ETAGS"; then
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 fi
 AC_SUBST([ETAGS])
 if test -z "$CSCOPE"; then
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 AC_SUBST([CSCOPE])
 AC_REQUIRE([_AM_SILENT_RULES])dnl
 dnl The testsuite driver may need to know about EXEEXT, so add the
 dnl 'am__EXEEXT' conditional if _AM_COMPILER_EXEEXT was seen.  This
 dnl macro is hooked onto _AC_COMPILER_EXEEXT early, see below.
@ -563,9 +542,47 @@ AC_CONFIG_COMMANDS_PRE(dnl
 [m4_provide_if([_AM_COMPILER_EXEEXT],
  [AM_CONDITIONAL([am__EXEEXT], [test -n "$EXEEXT"])])])dnl
-AC_REQUIRE([_AM_PROG_RM_F])
+# POSIX will say in a future version that running "rm -f" with no argument
-AC_REQUIRE([_AM_PROG_XARGS_N])
+# is OK; and we want to be able to make that assumption in our Makefile
 # recipes.  So use an aggressive probe to check that the usage we want is
 # actually supported "in the wild" to an acceptable degree.
 # See automake bug#10828.
 # To make any issue more visible, cause the running configure to be aborted
 # by default if the 'rm' program in use doesn't match our expectations; the
 # user can still override this though.
 if rm -f && rm -fr && rm -rf; then : OK; else
  cat >&2 <<'END'
 Oops!
 Your 'rm' program seems unable to run without file operands specified
 on the command line, even when the '-f' option is present.  This is contrary
 to the behaviour of most rm programs out there, and not conforming with
 the upcoming POSIX standard: <http://austingroupbugs.net/view.php?id=542>
 Please tell bug-automake@gnu.org about your system, including the value
 of your $PATH and any error possibly output before this message.  This
 can help us improve future automake versions.
 END
  if test x"$ACCEPT_INFERIOR_RM_PROGRAM" = x"yes"; then
    echo 'Configuration will proceed anyway, since you have set the' >&2
    echo 'ACCEPT_INFERIOR_RM_PROGRAM variable to "yes"' >&2
    echo >&2
  else
    cat >&2 <<'END'
 Aborting the configuration process, to ensure you take notice of the issue.
 You can download and install GNU coreutils to get an 'rm' implementation
 that behaves properly: <https://www.gnu.org/software/coreutils/>.
 If you want to complete the configuration process using your problematic
 'rm' anyway, export the environment variable ACCEPT_INFERIOR_RM_PROGRAM
 to "yes", and re-run configure.
 END
    AC_MSG_ERROR([Your 'rm' program is bad, sorry.])
  fi
 fi
 dnl The trailing newline in this macro's definition is deliberate, for
 dnl backward compatibility and to allow trailing 'dnl'-style comments
 dnl after the AM_INIT_AUTOMAKE invocation. See automake bug#16841.
@ -598,7 +615,7 @@ for _am_header in $config_headers :; do
 done
 echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_count])
-# Copyright (C) 2001-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -619,7 +636,7 @@ if test x"${install_sh+set}" != xset; then
 fi
 AC_SUBST([install_sh])])
-# Copyright (C) 2003-2025 Free Software Foundation, Inc.
+# Copyright (C) 2003-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -641,7 +658,7 @@ AC_SUBST([am__leading_dot])])
 # Add --enable-maintainer-mode option to configure.         -*- Autoconf -*-
 # From Jim Meyering
-# Copyright (C) 1996-2025 Free Software Foundation, Inc.
+# Copyright (C) 1996-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -676,7 +693,7 @@ AC_MSG_CHECKING([whether to enable maintainer-specific portions of Makefiles])
 # Check to see how 'make' treats includes.	            -*- Autoconf -*-
-# Copyright (C) 2001-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -719,7 +736,7 @@ AC_SUBST([am__quote])])
 # Fake the existence of programs that GNU maintainers use.  -*- Autoconf -*-
-# Copyright (C) 1997-2025 Free Software Foundation, Inc.
+# Copyright (C) 1997-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -740,7 +757,12 @@ AC_DEFUN([AM_MISSING_HAS_RUN],
 [AC_REQUIRE([AM_AUX_DIR_EXPAND])dnl
 AC_REQUIRE_AUX_FILE([missing])dnl
 if test x"${MISSING+set}" != xset; then
-  MISSING="\${SHELL} '$am_aux_dir/missing'"
+  case $am_aux_dir in
  *\ * | *\	*)
    MISSING="\${SHELL} \"$am_aux_dir/missing\"" ;;
  *)
    MISSING="\${SHELL} $am_aux_dir/missing" ;;
  esac
 fi
 # Use eval to expand $SHELL
 if eval "$MISSING --is-lightweight"; then
@ -753,7 +775,7 @@ fi
 # Helper functions for option handling.                     -*- Autoconf -*-
-# Copyright (C) 2001-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -782,7 +804,7 @@ AC_DEFUN([_AM_SET_OPTIONS],
 AC_DEFUN([_AM_IF_OPTION],
 [m4_ifset(_AM_MANGLE_OPTION([$1]), [$2], [$3])])
-# Copyright (C) 1999-2025 Free Software Foundation, Inc.
+# Copyright (C) 1999-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -814,10 +836,7 @@ AC_CACHE_CHECK(
      break
    fi
  done
-  # aligned with autoconf, so not including core; see bug#72225.
+  rm -f core conftest*
  rm -f -r a.out a.exe b.out conftest.$ac_ext conftest.$ac_objext \
    conftest.dSYM conftest1.$ac_ext conftest1.$ac_objext conftest1.dSYM \
    conftest2.$ac_ext conftest2.$ac_objext conftest2.dSYM
  unset am_i])
 if test "$am_cv_prog_cc_c_o" != yes; then
   # Losing compiler, so override with the script.
@ -832,23 +851,7 @@ AC_LANG_POP([C])])
 # For backward compatibility.
 AC_DEFUN_ONCE([AM_PROG_CC_C_O], [AC_REQUIRE([AC_PROG_CC])])
-# Copyright (C) 2022-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 # _AM_PROG_RM_F
 # ---------------
 # Check whether 'rm -f' without any arguments works.
 # https://bugs.gnu.org/10828
 AC_DEFUN([_AM_PROG_RM_F],
 [am__rm_f_notfound=
 AS_IF([(rm -f && rm -fr && rm -rf) 2>/dev/null], [], [am__rm_f_notfound='""'])
 AC_SUBST(am__rm_f_notfound)
 ])
 # Copyright (C) 2001-2025 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -867,181 +870,26 @@ AC_DEFUN([AM_RUN_LOG],
 # Check to make sure that the build environment is sane.    -*- Autoconf -*-
-# Copyright (C) 1996-2025 Free Software Foundation, Inc.
+# Copyright (C) 1996-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 # _AM_SLEEP_FRACTIONAL_SECONDS
 # ----------------------------
 AC_DEFUN([_AM_SLEEP_FRACTIONAL_SECONDS], [dnl
 AC_CACHE_CHECK([whether sleep supports fractional seconds],
               am_cv_sleep_fractional_seconds, [dnl
 AS_IF([sleep 0.001 2>/dev/null], [am_cv_sleep_fractional_seconds=yes],
                                 [am_cv_sleep_fractional_seconds=no])
 ])])
 # _AM_FILESYSTEM_TIMESTAMP_RESOLUTION
 # -----------------------------------
 # Determine the filesystem's resolution for file modification
 # timestamps.  The coarsest we know of is FAT, with a resolution
 # of only two seconds, even with the most recent "exFAT" extensions.
 # The finest (e.g. ext4 with large inodes, XFS, ZFS) is one
 # nanosecond, matching clock_gettime.  However, it is probably not
 # possible to delay execution of a shell script for less than one
 # millisecond, due to process creation overhead and scheduling
 # granularity, so we don't check for anything finer than that. (See below.)
 AC_DEFUN([_AM_FILESYSTEM_TIMESTAMP_RESOLUTION], [dnl
 AC_REQUIRE([_AM_SLEEP_FRACTIONAL_SECONDS])
 AC_CACHE_CHECK([filesystem timestamp resolution],
               am_cv_filesystem_timestamp_resolution, [dnl
 # Default to the worst case.
 am_cv_filesystem_timestamp_resolution=2
 # Only try to go finer than 1 sec if sleep can do it.
 # Don't try 1 sec, because if 0.01 sec and 0.1 sec don't work,
 # - 1 sec is not much of a win compared to 2 sec, and
 # - it takes 2 seconds to perform the test whether 1 sec works.
 # 
 # Instead, just use the default 2s on platforms that have 1s resolution,
 # accept the extra 1s delay when using $sleep in the Automake tests, in
 # exchange for not incurring the 2s delay for running the test for all
 # packages.
 #
 am_try_resolutions=
 if test "$am_cv_sleep_fractional_seconds" = yes; then
  # Even a millisecond often causes a bunch of false positives,
  # so just try a hundredth of a second. The time saved between .001 and
  # .01 is not terribly consequential.
  am_try_resolutions="0.01 0.1 $am_try_resolutions"
 fi
 # In order to catch current-generation FAT out, we must *modify* files
 # that already exist; the *creation* timestamp is finer.  Use names
 # that make ls -t sort them differently when they have equal
 # timestamps than when they have distinct timestamps, keeping
 # in mind that ls -t prints the *newest* file first.
 rm -f conftest.ts?
 : > conftest.ts1
 : > conftest.ts2
 : > conftest.ts3
 # Make sure ls -t actually works.  Do 'set' in a subshell so we don't
 # clobber the current shell's arguments. (Outer-level square brackets
 # are removed by m4; they're present so that m4 does not expand
 # <dollar><star>; be careful, easy to get confused.)
 if (
     set X `[ls -t conftest.ts[12]]` &&
     {
       test "$[]*" != "X conftest.ts1 conftest.ts2" ||
       test "$[]*" != "X conftest.ts2 conftest.ts1";
     }
 ); then :; else
  # If neither matched, then we have a broken ls.  This can happen
  # if, for instance, CONFIG_SHELL is bash and it inherits a
  # broken ls alias from the environment.  This has actually
  # happened.  Such a system could not be considered "sane".
  _AS_ECHO_UNQUOTED(
    ["Bad output from ls -t: \"`[ls -t conftest.ts[12]]`\""],
    [AS_MESSAGE_LOG_FD])
  AC_MSG_FAILURE([ls -t produces unexpected output.
 Make sure there is not a broken ls alias in your environment.])
 fi
 for am_try_res in $am_try_resolutions; do
  # Any one fine-grained sleep might happen to cross the boundary
  # between two values of a coarser actual resolution, but if we do
  # two fine-grained sleeps in a row, at least one of them will fall
  # entirely within a coarse interval.
  echo alpha > conftest.ts1
  sleep $am_try_res
  echo beta > conftest.ts2
  sleep $am_try_res
  echo gamma > conftest.ts3
  # We assume that 'ls -t' will make use of high-resolution
  # timestamps if the operating system supports them at all.
  if (set X `ls -t conftest.ts?` &&
      test "$[]2" = conftest.ts3 &&
      test "$[]3" = conftest.ts2 &&
      test "$[]4" = conftest.ts1); then
    #
    # Ok, ls -t worked. If we're at a resolution of 1 second, we're done,
    # because we don't need to test make.
    make_ok=true
    if test $am_try_res != 1; then
      # But if we've succeeded so far with a subsecond resolution, we
      # have one more thing to check: make. It can happen that
      # everything else supports the subsecond mtimes, but make doesn't;
      # notably on macOS, which ships make 3.81 from 2006 (the last one
      # released under GPLv2). https://bugs.gnu.org/68808
      # 
      # We test $MAKE if it is defined in the environment, else "make".
      # It might get overridden later, but our hope is that in practice
      # it does not matter: it is the system "make" which is (by far)
      # the most likely to be broken, whereas if the user overrides it,
      # probably they did so with a better, or at least not worse, make.
      # https://lists.gnu.org/archive/html/automake/2024-06/msg00051.html
      #
      # Create a Makefile (real tab character here):
      rm -f conftest.mk
      echo 'conftest.ts1: conftest.ts2' >conftest.mk
      echo '	touch conftest.ts2' >>conftest.mk
      #
      # Now, running
      #   touch conftest.ts1; touch conftest.ts2; make
      # should touch ts1 because ts2 is newer. This could happen by luck,
      # but most often, it will fail if make's support is insufficient. So
      # test for several consecutive successes.
      #
      # (We reuse conftest.ts[12] because we still want to modify existing
      # files, not create new ones, per above.)
      n=0
      make=${MAKE-make}
      until test $n -eq 3; do
        echo one > conftest.ts1
        sleep $am_try_res
        echo two > conftest.ts2 # ts2 should now be newer than ts1
        if $make -f conftest.mk | grep 'up to date' >/dev/null; then
          make_ok=false
          break # out of $n loop
        fi
        n=`expr $n + 1`
      done
    fi
    #
    if $make_ok; then
      # Everything we know to check worked out, so call this resolution good.
      am_cv_filesystem_timestamp_resolution=$am_try_res
      break # out of $am_try_res loop
    fi
    # Otherwise, we'll go on to check the next resolution.
  fi
 done
 rm -f conftest.ts?
 # (end _am_filesystem_timestamp_resolution)
 ])])
 # AM_SANITY_CHECK
 # ---------------
 AC_DEFUN([AM_SANITY_CHECK],
-[AC_REQUIRE([_AM_FILESYSTEM_TIMESTAMP_RESOLUTION])
+[AC_MSG_CHECKING([whether build environment is sane])
 # This check should not be cached, as it may vary across builds of
 # different projects.
 AC_MSG_CHECKING([whether build environment is sane])
 # Reject unsafe characters in $srcdir or the absolute working directory
 # name.  Accept space and tab only in the latter.
 am_lf='
 '
 case `pwd` in
  *[[\\\"\#\$\&\'\`$am_lf]]*)
    AC_MSG_RESULT([no])
    AC_MSG_ERROR([unsafe absolute working directory name]);;
 esac
 case $srcdir in
  *[[\\\"\#\$\&\'\`$am_lf\ \	]]*)
    AC_MSG_RESULT([no])
    AC_MSG_ERROR([unsafe srcdir value: '$srcdir']);;
 esac
@ -1050,40 +898,49 @@ esac
 # symlink; some systems play weird games with the mod time of symlinks
 # (eg FreeBSD returns the mod time of the symlink's containing
 # directory).
-am_build_env_is_sane=no
+if (
-am_has_slept=no
+   am_has_slept=no
-rm -f conftest.file
+   for am_try in 1 2; do
-for am_try in 1 2; do
+     echo "timestamp, slept: $am_has_slept" > conftest.file
-  echo "timestamp, slept: $am_has_slept" > conftest.file
+     set X `ls -Lt "$srcdir/configure" conftest.file 2> /dev/null`
-  if (
+     if test "$[*]" = "X"; then
-    set X `ls -Lt "$srcdir/configure" conftest.file 2> /dev/null`
+	# -L didn't work.
-    if test "$[]*" = "X"; then
+	set X `ls -t "$srcdir/configure" conftest.file`
-      # -L didn't work.
+     fi
-      set X `ls -t "$srcdir/configure" conftest.file`
+     if test "$[*]" != "X $srcdir/configure conftest.file" \
-    fi
+	&& test "$[*]" != "X conftest.file $srcdir/configure"; then
    test "$[]2" = conftest.file
  ); then
    am_build_env_is_sane=yes
    break
  fi
  # Just in case.
  sleep "$am_cv_filesystem_timestamp_resolution"
  am_has_slept=yes
 done
-AC_MSG_RESULT([$am_build_env_is_sane])
+	# If neither matched, then we have a broken ls.  This can happen
-if test "$am_build_env_is_sane" = no; then
+	# if, for instance, CONFIG_SHELL is bash and it inherits a
-  AC_MSG_ERROR([newly created file is older than distributed files!
+	# broken ls alias from the environment.  This has actually
 	# happened.  Such a system could not be considered "sane".
 	AC_MSG_ERROR([ls -t appears to fail.  Make sure there is not a broken
  alias in your environment])
     fi
     if test "$[2]" = conftest.file || test $am_try -eq 2; then
       break
     fi
     # Just in case.
     sleep 1
     am_has_slept=yes
   done
   test "$[2]" = conftest.file
   )
 then
   # Ok.
   :
 else
   AC_MSG_ERROR([newly created file is older than distributed files!
 Check your system clock])
 fi
-
+AC_MSG_RESULT([yes])
 # If we didn't sleep, we still need to ensure time stamps of config.status and
 # generated files are strictly newer.
 am_sleep_pid=
-AS_IF([test -e conftest.file || grep 'slept: no' conftest.file >/dev/null 2>&1],, [dnl
+if grep 'slept: no' conftest.file >/dev/null 2>&1; then
-  ( sleep "$am_cv_filesystem_timestamp_resolution" ) &
+  ( sleep 1 ) &
  am_sleep_pid=$!
-])
+fi
 AC_CONFIG_COMMANDS_PRE(
  [AC_MSG_CHECKING([that generated files are newer than configure])
   if test -n "$am_sleep_pid"; then
@ -1094,18 +951,18 @@ AC_CONFIG_COMMANDS_PRE(
 rm -f conftest.file
 ])
-# Copyright (C) 2009-2025 Free Software Foundation, Inc.
+# Copyright (C) 2009-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
-# _AM_SILENT_RULES
+# AM_SILENT_RULES([DEFAULT])
-# ----------------
+# --------------------------
-# Enable less verbose build rules support.
+# Enable less verbose build rules; with the default set to DEFAULT
-AC_DEFUN([_AM_SILENT_RULES],
+# ("yes" being less verbose, "no" or empty being verbose).
-[AM_DEFAULT_VERBOSITY=1
+AC_DEFUN([AM_SILENT_RULES],
-AC_ARG_ENABLE([silent-rules], [dnl
+[AC_ARG_ENABLE([silent-rules], [dnl
 AS_HELP_STRING(
  [--enable-silent-rules],
  [less verbose build output (undo: "make V=1")])
@ -1113,6 +970,11 @@ AS_HELP_STRING(
  [--disable-silent-rules],
  [verbose build output (undo: "make V=0")])dnl
 ])
 case $enable_silent_rules in @%:@ (((
  yes) AM_DEFAULT_VERBOSITY=0;;
   no) AM_DEFAULT_VERBOSITY=1;;
    *) AM_DEFAULT_VERBOSITY=m4_if([$1], [yes], [0], [1]);;
 esac
 dnl
 dnl A few 'make' implementations (e.g., NonStop OS and NextStep)
 dnl do not support nested variable expansions.
@ -1131,21 +993,6 @@ am__doit:
 else
  am_cv_make_support_nested_variables=no
 fi])
 AC_SUBST([AM_V])dnl
 AM_SUBST_NOTMAKE([AM_V])dnl
 AC_SUBST([AM_DEFAULT_V])dnl
 AM_SUBST_NOTMAKE([AM_DEFAULT_V])dnl
 AC_SUBST([AM_DEFAULT_VERBOSITY])dnl
 AM_BACKSLASH='\'
 AC_SUBST([AM_BACKSLASH])dnl
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 dnl Delay evaluation of AM_DEFAULT_VERBOSITY to the end to allow multiple calls
 dnl to AM_SILENT_RULES to change the default value.
 AC_CONFIG_COMMANDS_PRE([dnl
 case $enable_silent_rules in @%:@ (((
  yes) AM_DEFAULT_VERBOSITY=0;;
   no) AM_DEFAULT_VERBOSITY=1;;
 esac
 if test $am_cv_make_support_nested_variables = yes; then
  dnl Using '$V' instead of '$(V)' breaks IRIX make.
  AM_V='$(V)'
@ -1154,22 +1001,17 @@ else
  AM_V=$AM_DEFAULT_VERBOSITY
  AM_DEFAULT_V=$AM_DEFAULT_VERBOSITY
 fi
-])dnl
+AC_SUBST([AM_V])dnl
 AM_SUBST_NOTMAKE([AM_V])dnl
 AC_SUBST([AM_DEFAULT_V])dnl
 AM_SUBST_NOTMAKE([AM_DEFAULT_V])dnl
 AC_SUBST([AM_DEFAULT_VERBOSITY])dnl
 AM_BACKSLASH='\'
 AC_SUBST([AM_BACKSLASH])dnl
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 ])
-# AM_SILENT_RULES([DEFAULT])
+# Copyright (C) 2001-2018 Free Software Foundation, Inc.
 # --------------------------
 # Set the default verbosity level to DEFAULT ("yes" being less verbose, "no" or
 # empty being verbose).
 AC_DEFUN([AM_SILENT_RULES],
 [AC_REQUIRE([_AM_SILENT_RULES])
 AM_DEFAULT_VERBOSITY=m4_if([$1], [yes], [0], [1])m4_newline
 dnl We intentionally force a newline after the assignment, since a) nothing
 dnl good can come of more text following, and b) that was the behavior
 dnl before 1.17. See https://bugs.gnu.org/72267.
 ])
 # Copyright (C) 2001-2025 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -1197,7 +1039,7 @@ fi
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 AC_SUBST([INSTALL_STRIP_PROGRAM])])
-# Copyright (C) 2006-2025 Free Software Foundation, Inc.
+# Copyright (C) 2006-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -1216,7 +1058,7 @@ AC_DEFUN([AM_SUBST_NOTMAKE], [_AM_SUBST_NOTMAKE($@)])
 # Check how to create a tarball.                            -*- Autoconf -*-
-# Copyright (C) 2004-2025 Free Software Foundation, Inc.
+# Copyright (C) 2004-2018 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@ -1262,19 +1104,15 @@ m4_if([$1], [v7],
      am_uid=`id -u || echo unknown`
      am_gid=`id -g || echo unknown`
      AC_MSG_CHECKING([whether UID '$am_uid' is supported by ustar format])
-      if test x$am_uid = xunknown; then
+      if test $am_uid -le $am_max_uid; then
-        AC_MSG_WARN([ancient id detected; assuming current UID is ok, but dist-ustar might not work])
+         AC_MSG_RESULT([yes])
      elif test $am_uid -le $am_max_uid; then
        AC_MSG_RESULT([yes])
      else
-        AC_MSG_RESULT([no])
+         AC_MSG_RESULT([no])
-        _am_tools=none
+         _am_tools=none
      fi
      AC_MSG_CHECKING([whether GID '$am_gid' is supported by ustar format])
-      if test x$gm_gid = xunknown; then
+      if test $am_gid -le $am_max_gid; then
-        AC_MSG_WARN([ancient id detected; assuming current GID is ok, but dist-ustar might not work])
+         AC_MSG_RESULT([yes])
      elif test $am_gid -le $am_max_gid; then
        AC_MSG_RESULT([yes])
      else
        AC_MSG_RESULT([no])
        _am_tools=none
@ -1351,28 +1189,8 @@ AC_SUBST([am__tar])
 AC_SUBST([am__untar])
 ]) # _AM_PROG_TAR
-# Copyright (C) 2022-2025 Free Software Foundation, Inc.
+m4_include([scripts/libtool.m4])
-#
+m4_include([scripts/ltoptions.m4])
-# This file is free software; the Free Software Foundation
+m4_include([scripts/ltsugar.m4])
-# gives unlimited permission to copy and/or distribute it,
+m4_include([scripts/ltversion.m4])
-# with or without modifications, as long as this notice is preserved.
+m4_include([scripts/lt~obsolete.m4])
 # _AM_PROG_XARGS_N
 # ----------------
 # Check whether 'xargs -n' works.  It should work everywhere, so the fallback
 # is not optimized at all as we never expect to use it.
 AC_DEFUN([_AM_PROG_XARGS_N],
 [AC_CACHE_CHECK([xargs -n works], am_cv_xargs_n_works, [dnl
 AS_IF([test "`echo 1 2 3 | xargs -n2 echo`" = "1 2
 3"], [am_cv_xargs_n_works=yes], [am_cv_xargs_n_works=no])])
 AS_IF([test "$am_cv_xargs_n_works" = yes], [am__xargs_n='xargs -n'], [dnl
  am__xargs_n='am__xargs_n () { shift; sed "s/ /\\n/g" | while read am__xargs_n_arg; do "$@" "$am__xargs_n_arg"; done; }'
 ])dnl
 AC_SUBST(am__xargs_n)
 ])
 m4_include([scripts/autoconf/libtool.m4])
 m4_include([scripts/autoconf/ltoptions.m4])
 m4_include([scripts/autoconf/ltsugar.m4])
 m4_include([scripts/autoconf/ltversion.m4])
 m4_include([scripts/autoconf/lt~obsolete.m4])
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@ -1,6 +1,7 @@
 /* arm_init.c - NEON optimised filter functions
 *
- * Copyright (c) 2018-2022 Cosmin Truta
+ * Copyright (c) 2018 Cosmin Truta
 * Copyright (c) 2014,2016 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
 *
@ -9,7 +10,9 @@
 * and license in png.h
 */
-/* This module requires POSIX 1003.1 functions. */
+/* Below, after checking __linux__, various non-C90 POSIX 1003.1 functions are
 * called.
 */
 #define _POSIX_SOURCE 1
 #include "../pngpriv.h"
@ -30,30 +33,25 @@
 * has partial support is contrib/arm-neon/linux.c - a generic Linux
 * implementation which reads /proc/cpufino.
 */
 #include <signal.h> /* for sig_atomic_t */
 #ifndef PNG_ARM_NEON_FILE
-#  if defined(__aarch64__) || defined(_M_ARM64)
+#  ifdef __linux__
-     /* ARM Neon is expected to be unconditionally available on ARM64. */
+#     define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
 #    error PNG_ARM_NEON_CHECK_SUPPORTED must not be defined on ARM64
 #  elif defined(__ARM_NEON__) || defined(__ARM_NEON)
     /* ARM Neon is expected to be available on the target CPU architecture. */
 #    error PNG_ARM_NEON_CHECK_SUPPORTED must not be defined on this CPU arch
 #  elif defined(__linux__)
 #    define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
 #  else
 #    error No support for run-time ARM Neon checking; use compile-time options
 #  endif
 #endif
 static int png_have_neon(png_structp png_ptr);
 #ifdef PNG_ARM_NEON_FILE
-#  include PNG_ARM_NEON_FILE
+
-#endif
+#include <signal.h> /* for sig_atomic_t */
 static int png_have_neon(png_structp png_ptr);
 #include PNG_ARM_NEON_FILE
 #else  /* PNG_ARM_NEON_FILE */
 #  error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
 #endif /* PNG_ARM_NEON_FILE */
 #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
-#  error ALIGNED_MEMORY is required; please define PNG_ALIGNED_MEMORY_SUPPORTED
+#  error "ALIGNED_MEMORY is required; set: -DPNG_ALIGNED_MEMORY_SUPPORTED"
 #endif
 void
--- a/arm/filter_neon.S
+++ b/arm/filter_neon.S
@ -1,60 +1,253 @@
-/* filter_neon.S - placeholder file
+
 /* filter_neon.S - NEON optimised filter functions
 *
- * Copyright (c) 2024 Cosmin Truta
+ * Copyright (c) 2018 Cosmin Truta
 * Copyright (c) 2014,2017 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
 */
 /* IMPORTANT NOTE:
 *
 * Historically, the hand-coded assembler implementation of Neon optimizations
 * in this module had not been in sync with the intrinsics-based implementation
 * in filter_neon_intrinsics.c and palette_neon_intrinsics.c, at least since
 * the introduction of riffled palette optimizations. Moreover, the assembler
 * code used to work on 32-bit ARM only, and it caused problems, even if empty,
 * on 64-bit ARM.
 *
 * All references to this module from our internal build scripts and projects
 * have been removed.
 *
 * For the external projects that might still expect this module to be present,
 * we leave this stub in place, for the remaining lifetime of libpng-1.6.x.
 * Everything should continue to function normally, as long as there are no
 * deliberate attempts to use the old hand-made assembler code. A build error
 * will be raised otherwise.
 */
 /* This is required to get the symbol renames, which are #defines, and the
 * definitions (or not) of PNG_ARM_NEON_OPT and PNG_ARM_NEON_IMPLEMENTATION.
 */
 #define PNG_VERSION_INFO_ONLY
 #include "../pngpriv.h"
 #if (defined(__linux__) || defined(__FreeBSD__)) && defined(__ELF__)
 .section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
 #endif
 #ifdef PNG_READ_SUPPORTED
 /* Assembler NEON support - only works for 32-bit ARM (i.e. it does not work for
 * ARM64).  The code in arm/filter_neon_intrinsics.c supports ARM64, however it
 * only works if -mfpu=neon is specified on the GCC command line.  See pngpriv.h
 * for the logic which sets PNG_USE_ARM_NEON_ASM:
 */
 #if PNG_ARM_NEON_IMPLEMENTATION == 2 /* hand-coded assembler */
 #if PNG_ARM_NEON_OPT > 0
-#if defined(__clang__)
+#ifdef __ELF__
-#define GNUC_VERSION 0 /* not gcc, although it might pretend to be */
+#   define ELF
 #elif defined(__GNUC__)
 #define GNUC_MAJOR (__GNUC__ + 0)
 #define GNUC_MINOR (__GNUC_MINOR__ + 0)
 #define GNUC_PATCHLEVEL (__GNUC_PATCHLEVEL__ + 0)
 #define GNUC_VERSION (GNUC_MAJOR * 10000 + GNUC_MINOR * 100 + GNUC_PATCHLEVEL)
 #else
-#define GNUC_VERSION 0 /* not gcc */
+#   define ELF @
 #endif
-#if (GNUC_VERSION > 0) && (GNUC_VERSION < 40300)
+        .arch armv7-a
-#error "PNG_ARM_NEON is not supported with gcc versions earlier than 4.3.0"
+        .fpu  neon
 #elif GNUC_VERSION == 40504
 #error "PNG_ARM_NEON is not supported with gcc version 4.5.4"
 #else
 #error "Please use 'arm/*_neon_intrinsics.c' for PNG_ARM_NEON support"
 #endif
 .macro  func    name, export=0
    .macro endfunc
 ELF     .size   \name, . - \name
        .endfunc
        .purgem endfunc
    .endm
        .text
        /* Explicitly specifying alignment here because some versions of
         * GAS don't align code correctly.  This is harmless in correctly
         * written versions of GAS.
         */
        .align 2
    .if \export
        .global \name
    .endif
 ELF     .type   \name, STT_FUNC
        .func   \name
 \name:
 .endm
 func    png_read_filter_row_sub4_neon, export=1
        ldr             r3,  [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
 1:
        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
        vadd.u8         d0,  d3,  d4
        vadd.u8         d1,  d0,  d5
        vadd.u8         d2,  d1,  d6
        vadd.u8         d3,  d2,  d7
        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
        subs            r3,  r3,  #16
        bgt             1b
        bx              lr
 endfunc
 func    png_read_filter_row_sub3_neon, export=1
        ldr             r3,  [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
        mov             r0,  r1
        mov             r2,  #3
        mov             r12, #12
        vld1.8          {q11},    [r0], r12
 1:
        vext.8          d5,  d22, d23, #3
        vadd.u8         d0,  d3,  d22
        vext.8          d6,  d22, d23, #6
        vadd.u8         d1,  d0,  d5
        vext.8          d7,  d23, d23, #1
        vld1.8          {q11},    [r0], r12
        vst1.32         {d0[0]},  [r1,:32], r2
        vadd.u8         d2,  d1,  d6
        vst1.32         {d1[0]},  [r1], r2
        vadd.u8         d3,  d2,  d7
        vst1.32         {d2[0]},  [r1], r2
        vst1.32         {d3[0]},  [r1], r2
        subs            r3,  r3,  #12
        bgt             1b
        bx              lr
 endfunc
 func    png_read_filter_row_up_neon, export=1
        ldr             r3,  [r0, #4]           @ rowbytes
 1:
        vld1.8          {q0}, [r1,:128]
        vld1.8          {q1}, [r2,:128]!
        vadd.u8         q0,  q0,  q1
        vst1.8          {q0}, [r1,:128]!
        subs            r3,  r3,  #16
        bgt             1b
        bx              lr
 endfunc
 func    png_read_filter_row_avg4_neon, export=1
        ldr             r12, [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
 1:
        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
        vld4.32         {d16[],d17[],d18[],d19[]},[r2,:128]!
        vhadd.u8        d0,  d3,  d16
        vadd.u8         d0,  d0,  d4
        vhadd.u8        d1,  d0,  d17
        vadd.u8         d1,  d1,  d5
        vhadd.u8        d2,  d1,  d18
        vadd.u8         d2,  d2,  d6
        vhadd.u8        d3,  d2,  d19
        vadd.u8         d3,  d3,  d7
        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
        subs            r12, r12, #16
        bgt             1b
        bx              lr
 endfunc
 func    png_read_filter_row_avg3_neon, export=1
        push            {r4,lr}
        ldr             r12, [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
        mov             r0,  r1
        mov             r4,  #3
        mov             lr,  #12
        vld1.8          {q11},    [r0], lr
 1:
        vld1.8          {q10},    [r2], lr
        vext.8          d5,  d22, d23, #3
        vhadd.u8        d0,  d3,  d20
        vext.8          d17, d20, d21, #3
        vadd.u8         d0,  d0,  d22
        vext.8          d6,  d22, d23, #6
        vhadd.u8        d1,  d0,  d17
        vext.8          d18, d20, d21, #6
        vadd.u8         d1,  d1,  d5
        vext.8          d7,  d23, d23, #1
        vld1.8          {q11},    [r0], lr
        vst1.32         {d0[0]},  [r1,:32], r4
        vhadd.u8        d2,  d1,  d18
        vst1.32         {d1[0]},  [r1], r4
        vext.8          d19, d21, d21, #1
        vadd.u8         d2,  d2,  d6
        vhadd.u8        d3,  d2,  d19
        vst1.32         {d2[0]},  [r1], r4
        vadd.u8         d3,  d3,  d7
        vst1.32         {d3[0]},  [r1], r4
        subs            r12, r12, #12
        bgt             1b
        pop             {r4,pc}
 endfunc
 .macro  paeth           rx,  ra,  rb,  rc
        vaddl.u8        q12, \ra, \rb           @ a + b
        vaddl.u8        q15, \rc, \rc           @ 2*c
        vabdl.u8        q13, \rb, \rc           @ pa
        vabdl.u8        q14, \ra, \rc           @ pb
        vabd.u16        q15, q12, q15           @ pc
        vcle.u16        q12, q13, q14           @ pa <= pb
        vcle.u16        q13, q13, q15           @ pa <= pc
        vcle.u16        q14, q14, q15           @ pb <= pc
        vand            q12, q12, q13           @ pa <= pb && pa <= pc
        vmovn.u16       d28, q14
        vmovn.u16       \rx, q12
        vbsl            d28, \rb, \rc
        vbsl            \rx, \ra, d28
 .endm
 func    png_read_filter_row_paeth4_neon, export=1
        ldr             r12, [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
        vmov.i8         d20, #0
 1:
        vld4.32         {d4[],d5[],d6[],d7[]},    [r1,:128]
        vld4.32         {d16[],d17[],d18[],d19[]},[r2,:128]!
        paeth           d0,  d3,  d16, d20
        vadd.u8         d0,  d0,  d4
        paeth           d1,  d0,  d17, d16
        vadd.u8         d1,  d1,  d5
        paeth           d2,  d1,  d18, d17
        vadd.u8         d2,  d2,  d6
        paeth           d3,  d2,  d19, d18
        vmov            d20, d19
        vadd.u8         d3,  d3,  d7
        vst4.32         {d0[0],d1[0],d2[0],d3[0]},[r1,:128]!
        subs            r12, r12, #16
        bgt             1b
        bx              lr
 endfunc
 func    png_read_filter_row_paeth3_neon, export=1
        push            {r4,lr}
        ldr             r12, [r0, #4]           @ rowbytes
        vmov.i8         d3,  #0
        vmov.i8         d4,  #0
        mov             r0,  r1
        mov             r4,  #3
        mov             lr,  #12
        vld1.8          {q11},    [r0], lr
 1:
        vld1.8          {q10},    [r2], lr
        paeth           d0,  d3,  d20, d4
        vext.8          d5,  d22, d23, #3
        vadd.u8         d0,  d0,  d22
        vext.8          d17, d20, d21, #3
        paeth           d1,  d0,  d17, d20
        vst1.32         {d0[0]},  [r1,:32], r4
        vext.8          d6,  d22, d23, #6
        vadd.u8         d1,  d1,  d5
        vext.8          d18, d20, d21, #6
        paeth           d2,  d1,  d18, d17
        vext.8          d7,  d23, d23, #1
        vld1.8          {q11},    [r0], lr
        vst1.32         {d1[0]},  [r1], r4
        vadd.u8         d2,  d2,  d6
        vext.8          d19, d21, d21, #1
        paeth           d3,  d2,  d19, d18
        vst1.32         {d2[0]},  [r1], r4
        vmov            d4,  d19
        vadd.u8         d3,  d3,  d7
        vst1.32         {d3[0]},  [r1], r4
        subs            r12, r12, #12
        bgt             1b
        pop             {r4,pc}
 endfunc
 #endif /* PNG_ARM_NEON_OPT > 0 */
-#endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 */
+#endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 (assembler) */
 #endif /* READ */
--- a/arm/filter_neon_intrinsics.c
+++ b/arm/filter_neon_intrinsics.c
@ -1,3 +1,4 @@
 /* filter_neon_intrinsics.c - NEON optimised filter functions
 *
 * Copyright (c) 2018 Cosmin Truta
@ -17,7 +18,7 @@
 /* This code requires -mfpu=neon on the command line: */
 #if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
-#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_ARM64)
+#if defined(_MSC_VER) && defined(_M_ARM64)
 #  include <arm64_neon.h>
 #else
 #  include <arm_neon.h>
--- a/arm/palette_neon_intrinsics.c
+++ b/arm/palette_neon_intrinsics.c
@ -1,3 +1,4 @@
 /* palette_neon_intrinsics.c - NEON optimised palette expansion functions
 *
 * Copyright (c) 2018-2019 Cosmin Truta
@ -13,7 +14,7 @@
 #if PNG_ARM_NEON_IMPLEMENTATION == 1
-#if defined(_MSC_VER) && !defined(__clang__) && defined(_M_ARM64)
+#if defined(_MSC_VER) && defined(_M_ARM64)
 #  include <arm64_neon.h>
 #else
 #  include <arm_neon.h>
@ -29,6 +30,8 @@ png_riffle_palette_neon(png_structrp png_ptr)
   int num_trans = png_ptr->num_trans;
   int i;
   png_debug(1, "in png_riffle_palette_neon");
   /* Initially black, opaque. */
   uint8x16x4_t w = {{
      vdupq_n_u8(0x00),
@ -37,8 +40,6 @@ png_riffle_palette_neon(png_structrp png_ptr)
      vdupq_n_u8(0xff),
   }};
   png_debug(1, "in png_riffle_palette_neon");
   /* First, riffle the RGB colours into an RGBA8 palette.
    * The alpha component is set to opaque for now.
    */
@ -63,13 +64,12 @@ png_do_expand_palette_rgba8_neon(png_structrp png_ptr, png_row_infop row_info,
 {
   png_uint_32 row_width = row_info->width;
   const png_uint_32 *riffled_palette =
-      png_aligncastconst(png_const_uint_32p, png_ptr->riffled_palette);
+      (const png_uint_32 *)png_ptr->riffled_palette;
-   const png_uint_32 pixels_per_chunk = 4;
+   const png_int_32 pixels_per_chunk = 4;
-   png_uint_32 i;
+   int i;
   png_debug(1, "in png_do_expand_palette_rgba8_neon");
   PNG_UNUSED(row)
   if (row_width < pixels_per_chunk)
      return 0;
@ -109,11 +109,10 @@ png_do_expand_palette_rgb8_neon(png_structrp png_ptr, png_row_infop row_info,
   png_uint_32 row_width = row_info->width;
   png_const_bytep palette = (png_const_bytep)png_ptr->palette;
   const png_uint_32 pixels_per_chunk = 8;
-   png_uint_32 i;
+   int i;
   png_debug(1, "in png_do_expand_palette_rgb8_neon");
   PNG_UNUSED(row)
   if (row_width <= pixels_per_chunk)
      return 0;
--- a/autogen.sh
+++ b/autogen.sh
@ -77,14 +77,13 @@ libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in
   config.sub configure depcomp install-sh ltmain.sh missing\
   test-driver"
 #
-# Files generated by versions of autoconf >2.68 or automake >1.13 (i.e. later
+# Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
 # versions than those required by configure.ac):
 libpng_autotools_extra="compile config.h.in~"
 #
 # These are separate because 'maintainer-clean' does not remove them.
-libpng_libtool_files="scripts/autoconf/libtool.m4 scripts/autoconf/ltoptions.m4\
+libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
-   scripts/autoconf/ltsugar.m4 scripts/autoconf/ltversion.m4\
+   scripts/ltsugar.m4 scripts/ltversion.m4 scripts/lt~obsolete.m4"
   scripts/autoconf/lt~obsolete.m4"
 libpng_autotools_dirs="autom4te.cache" # not required
 #
--- a/ci/.shellcheckrc
+++ b/ci/.shellcheckrc
@ -1,11 +0,0 @@
 # Disable the "expressions don't expand in single quotes, use double quotes"
 # advice. We need the regular expressions to remain uninterpolated.
 disable=SC2016
 # Disable the "variable appears unused" warning caused by the use of getopts
 # with an obligatory (but unused) variable name in the main function.
 disable=SC2034
 # Disable all the "quote to prevent globbing or word splitting" advice.
 # We need word splitting for well-known variables like MAKEFLAGS and CFLAGS.
 disable=SC2086,SC2206
--- a/ci/LICENSE_MIT.txt
+++ b/ci/LICENSE_MIT.txt
@ -1,19 +0,0 @@
 MIT License
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 The above copyright notice and this permission notice shall be included in all
 copies or substantial portions of the Software.
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
--- a/ci/README.md
+++ b/ci/README.md
@ -1,25 +0,0 @@
 Scripts for the Continuous Integration of the PNG Reference Library
 ===================================================================
 Copyright Notice
 ----------------
 Copyright (c) 2019-2025 Cosmin Truta.
 Use, modification and distribution are subject to the MIT License.
 Please see the accompanying file `LICENSE_MIT.txt` or visit
 https://opensource.org/license/mit
 File List
 ---------
    LICENSE_MIT.txt         ==>  The License file
    README.md               ==>  This file
    ci_lint.sh              ==>  Lint the source code
    ci_shellify.sh          ==>  Convert select definitions to shell syntax
    ci_verify_cmake.sh      ==>  Verify the build driven by CMakeLists.txt
    ci_verify_configure.sh  ==>  Verify the build driven by configure
    ci_verify_makefiles.sh  ==>  Verify the build driven by scripts/makefile.*
    ci_verify_version.sh    ==>  Verify the consistency of version definitions
    lib/ci.lib.sh           ==>  Shell utilities for the main ci_*.sh scripts
    targets/*/ci_env.*.sh   ==>  Shell environments for cross-platform testing
--- a/ci/ci_lint.sh
+++ b/ci/ci_lint.sh
@ -1,142 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/lib/ci.lib.sh"
 cd "$CI_TOPLEVEL_DIR"
 # Initialize the global constants CI_{...}{CHECK,CHECKER,LINT}.
 CI_SHELLCHECK="${CI_SHELLCHECK:-shellcheck}"
 CI_EDITORCONFIG_CHECKER="${CI_EDITORCONFIG_CHECKER:-editorconfig-checker}"
 CI_YAMLLINT="${CI_YAMLLINT:-yamllint}"
 # Initialize the global lint status.
 CI_LINT_STATUS=0
 function ci_init_lint {
    ci_info "## START OF LINTING ##"
    local my_program
    # Complete the initialization of CI_SHELLCHECK.
    # Set it to the empty string if the shellcheck program is unavailable.
    my_program="$(command -v "$CI_SHELLCHECK")" || {
        ci_warn "program not found: '$CI_SHELLCHECK'"
    }
    CI_SHELLCHECK="$my_program"
    # Complete the initialization of CI_EDITORCONFIG_CHECKER.
    # Set it to the empty string if the editorconfig-checker program is unavailable.
    my_program="$(command -v "$CI_EDITORCONFIG_CHECKER")" || {
        ci_warn "program not found: '$CI_EDITORCONFIG_CHECKER'"
    }
    CI_EDITORCONFIG_CHECKER="$my_program"
    # Complete the initialization of CI_YAMLLINT.
    # Set it to the empty string if the yamllint program is unavailable.
    my_program="$(command -v "$CI_YAMLLINT")" || {
        ci_warn "program not found: '$CI_YAMLLINT'"
    }
    CI_YAMLLINT="$my_program"
 }
 function ci_finish_lint {
    ci_info "## END OF LINTING ##"
    if [[ $CI_LINT_STATUS -eq 0 ]]
    then
        ci_info "## SUCCESS ##"
    else
        ci_info "linting failed"
    fi
    return "$CI_LINT_STATUS"
 }
 function ci_lint_ci_scripts {
    [[ -x $CI_SHELLCHECK ]] || {
        ci_warn "## NOT LINTING: CI scripts ##"
        return 0
    }
    ci_info "## LINTING: CI scripts ##"
    ci_spawn "$CI_SHELLCHECK" --version
    find ./ci -name "ci_*.sh" -not -name "ci_env.*.sh" | {
        local my_file
        while IFS="" read -r my_file
        do
            ci_spawn "$CI_SHELLCHECK" -x "$my_file" || {
                # Linting failed.
                return 1
            }
        done
    }
 }
 function ci_lint_text_files {
    [[ -x $CI_EDITORCONFIG_CHECKER ]] || {
        ci_warn "## NOT LINTING: text files ##"
        return 0
    }
    ci_info "## LINTING: text files ##"
    ci_spawn "$CI_EDITORCONFIG_CHECKER" --version
    ci_spawn "$CI_EDITORCONFIG_CHECKER" --config .editorconfig-checker.json || {
        # Linting failed.
        return 1
    }
 }
 function ci_lint_yaml_files {
    [[ -x $CI_YAMLLINT ]] || {
        ci_warn "## NOT LINTING: YAML files ##"
        return 0
    }
    ci_info "## LINTING: YAML files ##"
    ci_spawn "$CI_YAMLLINT" --version
    # Considering that the YAML format is an extension of the JSON format,
    # we can lint both the YAML files and the plain JSON files here.
    find . \( -iname "*.yml" -o -iname "*.yaml" -o -iname "*.json" \) -not -path "./out/*" | {
        local my_file
        while IFS="" read -r my_file
        do
            ci_spawn "$CI_YAMLLINT" --strict "$my_file" || {
                # Linting failed.
                return 1
            }
        done
    }
 }
 function ci_lint {
    ci_init_lint
    ci_lint_ci_scripts || CI_LINT_STATUS=1
    ci_lint_text_files || CI_LINT_STATUS=1
    ci_lint_yaml_files || CI_LINT_STATUS=1
    # TODO: ci_lint_png_files, etc.
    ci_finish_lint
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>]"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] || {
        echo >&2 "error: unexpected argument: '$1'"
        usage 2
    }
    # And... go!
    ci_lint
 }
 main "$@"
--- a/ci/ci_verify_cmake.sh
+++ b/ci/ci_verify_cmake.sh
@ -1,209 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/lib/ci.lib.sh"
 cd "$CI_TOPLEVEL_DIR"
 CI_SRC_DIR="$CI_TOPLEVEL_DIR"
 CI_OUT_DIR="$CI_TOPLEVEL_DIR/out"
 CI_BUILD_DIR="$CI_OUT_DIR/ci_verify_cmake.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.build"
 CI_INSTALL_DIR="$CI_OUT_DIR/ci_verify_cmake.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.install"
 function ci_init_build {
    # Ensure that the mandatory variables are initialized.
    CI_CMAKE="${CI_CMAKE:-cmake}"
    CI_CTEST="${CI_CTEST:-ctest}"
    CI_CMAKE_BUILD_TYPE="${CI_CMAKE_BUILD_TYPE:-Release}"
    if [[ $CI_CMAKE_GENERATOR == "Visual Studio"* ]]
    then
        # Clean up incidental mixtures of Windows and Bash-on-Windows
        # environment variables, to avoid confusing MSBuild.
        [[ $TEMP && ( $Temp || $temp ) ]] && unset TEMP
        [[ $TMP && ( $Tmp || $tmp ) ]] && unset TMP
        # Ensure that CI_CMAKE_GENERATOR_PLATFORM is initialized for this generator.
        [[ $CI_CMAKE_GENERATOR_PLATFORM ]] || {
            ci_err_internal "missing \$CI_CMAKE_GENERATOR_PLATFORM"
        }
    elif [[ -x $(command -v ninja) ]]
    then
        CI_CMAKE_GENERATOR="${CI_CMAKE_GENERATOR:-Ninja}"
    fi
 }
 function ci_trace_build {
    ci_info "## START OF CONFIGURATION ##"
    ci_info "build arch: $CI_BUILD_ARCH"
    ci_info "build system: $CI_BUILD_SYSTEM"
    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
        ci_info "target arch: $CI_TARGET_ARCH"
        ci_info "target system: $CI_TARGET_SYSTEM"
    }
    ci_info "source directory: $CI_SRC_DIR"
    ci_info "build directory: $CI_BUILD_DIR"
    ci_info "install directory: $CI_INSTALL_DIR"
    ci_info "environment option: \$CI_CMAKE: '$CI_CMAKE'"
    ci_info "environment option: \$CI_CMAKE_GENERATOR: '$CI_CMAKE_GENERATOR'"
    ci_info "environment option: \$CI_CMAKE_GENERATOR_PLATFORM: '$CI_CMAKE_GENERATOR_PLATFORM'"
    ci_info "environment option: \$CI_CMAKE_BUILD_TYPE: '$CI_CMAKE_BUILD_TYPE'"
    ci_info "environment option: \$CI_CMAKE_BUILD_FLAGS: '$CI_CMAKE_BUILD_FLAGS'"
    ci_info "environment option: \$CI_CMAKE_TOOLCHAIN_FILE: '$CI_CMAKE_TOOLCHAIN_FILE'"
    ci_info "environment option: \$CI_CMAKE_VARS: '$CI_CMAKE_VARS'"
    ci_info "environment option: \$CI_CTEST: '$CI_CTEST'"
    ci_info "environment option: \$CI_CTEST_FLAGS: '$CI_CTEST_FLAGS'"
    ci_info "environment option: \$CI_CC: '$CI_CC'"
    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
    ci_info "environment option: \$CI_AR: '$CI_AR'"
    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
    ci_info "environment option: \$CI_FORCE: '$CI_FORCE'"
    ci_info "environment option: \$CI_NO_BUILD: '$CI_NO_BUILD'"
    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
    ci_info "executable: \$CI_CMAKE: $(command -V "$CI_CMAKE")"
    ci_info "executable: \$CI_CTEST: $(command -V "$CI_CTEST")"
    [[ $CI_CC ]] && {
        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
    }
    [[ $CI_AR ]] && {
        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
    }
    [[ $CI_RANLIB ]] && {
        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
    }
    ci_info "## END OF CONFIGURATION ##"
 }
 function ci_cleanup_old_build {
    ci_info "## START OF PRE-BUILD CLEANUP ##"
    [[ ! -e $CI_BUILD_DIR && ! -e $CI_INSTALL_DIR ]] || {
        ci_spawn rm -fr "$CI_BUILD_DIR"
        ci_spawn rm -fr "$CI_INSTALL_DIR"
    }
    ci_info "## END OF PRE-BUILD CLEANUP ##"
 }
 function ci_build {
    ci_info "## START OF BUILD ##"
    # Adjust the CI environment variables, as needed.
    CI_CMAKE="$(command -v "$CI_CMAKE")" || ci_err "bad or missing \$CI_CMAKE"
    ci_spawn "$CI_CMAKE" --version
    CI_CTEST="$(command -v "$CI_CTEST")" || ci_err "bad or missing \$CI_CTEST"
    ci_spawn "$CI_CTEST" --version
    [[ $CI_CMAKE_GENERATOR == *"Ninja"* ]] && {
        CI_NINJA="$(command -v ninja)" || ci_err "bad or missing ninja, no pun intended"
        ci_spawn "$CI_NINJA" --version
    }
    [[ $CI_AR ]] && {
        # Use the full path of CI_AR to work around a mysterious CMake error.
        CI_AR="$(command -v "$CI_AR")" || ci_err "bad or missing \$CI_AR"
    }
    [[ $CI_RANLIB ]] && {
        # Use the full path of CI_RANLIB to work around a mysterious CMake error.
        CI_RANLIB="$(command -v "$CI_RANLIB")" || ci_err "bad or missing \$CI_RANLIB"
    }
    # Export the CMake environment variables.
    [[ $CI_CMAKE_GENERATOR ]] && {
        ci_spawn export CMAKE_GENERATOR="$CI_CMAKE_GENERATOR"
    }
    [[ $CI_CMAKE_GENERATOR_PLATFORM ]] && {
        ci_spawn export CMAKE_GENERATOR_PLATFORM="$CI_CMAKE_GENERATOR_PLATFORM"
    }
    # Initialize and populate the local arrays.
    local all_cmake_vars=()
    local all_cmake_build_flags=()
    local all_ctest_flags=()
    [[ $CI_CMAKE_TOOLCHAIN_FILE ]] && {
        all_cmake_vars+=("-DCMAKE_TOOLCHAIN_FILE=$CI_CMAKE_TOOLCHAIN_FILE")
    }
    [[ $CI_CC ]] && {
        all_cmake_vars+=("-DCMAKE_C_COMPILER=$CI_CC")
    }
    [[ $CI_CC_FLAGS || $CI_SANITIZERS ]] && {
        [[ $CI_SANITIZERS ]] && CI_CC_FLAGS+="${CI_CC_FLAGS:+" "}-fsanitize=$CI_SANITIZERS"
        all_cmake_vars+=("-DCMAKE_C_FLAGS=$CI_CC_FLAGS")
    }
    [[ $CI_AR ]] && {
        all_cmake_vars+=("-DCMAKE_AR=$CI_AR")
    }
    [[ $CI_RANLIB ]] && {
        all_cmake_vars+=("-DCMAKE_RANLIB=$CI_RANLIB")
    }
    all_cmake_vars+=("-DCMAKE_BUILD_TYPE=$CI_CMAKE_BUILD_TYPE")
    all_cmake_vars+=("-DCMAKE_VERBOSE_MAKEFILE=ON")
    all_cmake_vars+=($CI_CMAKE_VARS)
    all_cmake_build_flags+=($CI_CMAKE_BUILD_FLAGS)
    all_ctest_flags+=($CI_CTEST_FLAGS)
    # And... build!
    ci_spawn mkdir -p "$CI_BUILD_DIR"
    # Spawn "cmake ...".
    ci_spawn "$CI_CMAKE" -B "$CI_BUILD_DIR" \
                         -S . \
                         -DCMAKE_INSTALL_PREFIX="$CI_INSTALL_DIR" \
                         "${all_cmake_vars[@]}"
    ci_expr $((CI_NO_BUILD)) || {
        # Spawn "cmake --build ...".
        ci_spawn "$CI_CMAKE" --build "$CI_BUILD_DIR" \
                             --config "$CI_CMAKE_BUILD_TYPE" \
                             "${all_cmake_build_flags[@]}"
    }
    ci_expr $((CI_NO_TEST)) || {
        # Spawn "ctest" if testing is not disabled.
        ci_spawn pushd "$CI_BUILD_DIR"
        ci_spawn "$CI_CTEST" --build-config "$CI_CMAKE_BUILD_TYPE" \
                             "${all_ctest_flags[@]}"
        ci_spawn popd
    }
    ci_expr $((CI_NO_INSTALL)) || {
        # Spawn "cmake --build ... --target install" if installation is not disabled.
        ci_spawn "$CI_CMAKE" --build "$CI_BUILD_DIR" \
                             --config "$CI_CMAKE_BUILD_TYPE" \
                             --target install \
                             "${all_cmake_build_flags[@]}"
    }
    ci_expr $((CI_NO_CLEAN)) || {
        # Spawn "make --build ... --target clean" if cleaning is not disabled.
        ci_spawn "$CI_CMAKE" --build "$CI_BUILD_DIR" \
                             --config "$CI_CMAKE_BUILD_TYPE" \
                             --target clean \
                             "${all_cmake_build_flags[@]}"
    }
    ci_info "## END OF BUILD ##"
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>]"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    # And... go!
    ci_init_build
    ci_trace_build
    [[ $# -eq 0 ]] || {
        echo >&2 "error: unexpected argument: '$1'"
        echo >&2 "note: this program accepts environment options only"
        usage 2
    }
    ci_cleanup_old_build
    ci_build
 }
 main "$@"
--- a/ci/ci_verify_configure.sh
+++ b/ci/ci_verify_configure.sh
@ -1,182 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/lib/ci.lib.sh"
 cd "$CI_TOPLEVEL_DIR"
 CI_SRC_DIR="$CI_TOPLEVEL_DIR"
 CI_OUT_DIR="$CI_TOPLEVEL_DIR/out"
 CI_BUILD_DIR="$CI_OUT_DIR/ci_verify_configure.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.build"
 CI_INSTALL_DIR="$CI_OUT_DIR/ci_verify_configure.$CI_TARGET_SYSTEM.$CI_TARGET_ARCH.install"
 function ci_init_build {
    # Ensure that the mandatory variables are initialized.
    CI_MAKE="${CI_MAKE:-make}"
    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] || {
        # For native builds, set CI_CC to "cc" by default if the cc command is available.
        # The configure script defaults CC to "gcc", which is not always a good idea.
        [[ -x $(command -v cc) ]] && CI_CC="${CI_CC:-cc}"
    }
    # Ensure that the CI_ variables that cannot be customized reliably are not initialized.
    [[ ! $CI_CONFIGURE_VARS ]] || {
        ci_err "unsupported: \$CI_CONFIGURE_VARS='$CI_CONFIGURE_VARS'"
    }
    [[ ! $CI_MAKE_VARS ]] || {
        ci_err "unsupported: \$CI_MAKE_VARS='$CI_MAKE_VARS'"
    }
 }
 function ci_trace_build {
    ci_info "## START OF CONFIGURATION ##"
    ci_info "build arch: $CI_BUILD_ARCH"
    ci_info "build system: $CI_BUILD_SYSTEM"
    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
        ci_info "target arch: $CI_TARGET_ARCH"
        ci_info "target system: $CI_TARGET_SYSTEM"
    }
    ci_info "source directory: $CI_SRC_DIR"
    ci_info "build directory: $CI_BUILD_DIR"
    ci_info "install directory: $CI_INSTALL_DIR"
    ci_info "environment option: \$CI_CONFIGURE_FLAGS: '$CI_CONFIGURE_FLAGS'"
    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
    ci_info "environment option: \$CI_CC: '$CI_CC'"
    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
    ci_info "environment option: \$CI_AR: '$CI_AR'"
    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
    ci_info "environment option: \$CI_LD: '$CI_LD'"
    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
    ci_info "environment option: \$CI_FORCE: '$CI_FORCE'"
    ci_info "environment option: \$CI_NO_BUILD: '$CI_NO_BUILD'"
    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
    ci_info "environment option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
    [[ $CI_CC ]] && {
        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
    }
    [[ $CI_CPP ]] && {
        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
    }
    [[ $CI_AR ]] && {
        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
    }
    [[ $CI_RANLIB ]] && {
        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
    }
    [[ $CI_LD ]] && {
        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
    }
    ci_info "## END OF CONFIGURATION ##"
 }
 function ci_cleanup_old_build {
    ci_info "## START OF PRE-BUILD CLEANUP ##"
    [[ ! -e $CI_BUILD_DIR && ! -e $CI_INSTALL_DIR ]] || {
        ci_spawn rm -fr "$CI_BUILD_DIR"
        ci_spawn rm -fr "$CI_INSTALL_DIR"
    }
    [[ ! -e "$CI_SRC_DIR/config.status" ]] || {
        ci_warn "unexpected build configuration file: '$CI_SRC_DIR/config.status'"
        if ci_expr $((CI_FORCE))
        then
            # Delete the old config and (possibly) the old build.
            ci_info "note: forcing an in-tree build cleanup"
            if [[ -f $CI_SRC_DIR/Makefile ]]
            then
                ci_spawn make -C "$CI_SRC_DIR" distclean
            else
                ci_spawn rm -fr "$CI_SRC_DIR"/config.{log,status}
            fi
        else
            # Alert the user, but do not delete their files.
            ci_warn "the configure script might fail"
            ci_info "hint: consider using the option \$CI_FORCE=1"
        fi
    }
    ci_info "## END OF PRE-BUILD CLEANUP ##"
 }
 function ci_build {
    ci_info "## START OF BUILD ##"
    # Export the configure build environment.
    [[ $CI_CC ]] && ci_spawn export CC="$CI_CC"
    [[ $CI_CC_FLAGS ]] && ci_spawn export CFLAGS="$CI_CC_FLAGS"
    [[ $CI_CPP ]] && ci_spawn export CPP="$CI_CPP"
    [[ $CI_CPP_FLAGS ]] && ci_spawn export CPPFLAGS="$CI_CPP_FLAGS"
    [[ $CI_AR ]] && ci_spawn export AR="$CI_AR"
    [[ $CI_RANLIB ]] && ci_spawn export RANLIB="$CI_RANLIB"
    [[ $CI_LD ]] && ci_spawn export LD="$CI_LD"
    [[ $CI_LD_FLAGS ]] && ci_spawn export LDFLAGS="$CI_LD_FLAGS"
    [[ $CI_SANITIZERS ]] && {
        ci_spawn export CFLAGS="${CFLAGS:-"-O2"} -fsanitize=$CI_SANITIZERS"
        ci_spawn export LDFLAGS="${LDFLAGS}${LDFLAGS:+" "}-fsanitize=$CI_SANITIZERS"
    }
    # Spawn "autogen.sh" if the configure script is not available.
    [[ -x "$CI_SRC_DIR/configure" ]] || {
        ci_spawn "$CI_SRC_DIR/autogen.sh" --maintainer
    }
    # And... build!
    ci_spawn mkdir -p "$CI_BUILD_DIR"
    ci_spawn cd "$CI_BUILD_DIR"
    # Spawn "configure".
    ci_spawn "$CI_SRC_DIR/configure" --prefix="$CI_INSTALL_DIR" $CI_CONFIGURE_FLAGS
    ci_expr $((CI_NO_BUILD)) || {
        # Spawn "make".
        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS
    }
    ci_expr $((CI_NO_TEST)) || {
        # Spawn "make test" if testing is not disabled.
        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS test
    }
    ci_expr $((CI_NO_INSTALL)) || {
        # Spawn "make install" if installation is not disabled.
        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS install
    }
    ci_expr $((CI_NO_CLEAN)) || {
        # Spawn "make clean" and "make distclean" if cleaning is not disabled.
        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS clean
        ci_spawn "$CI_MAKE" $CI_MAKE_FLAGS distclean
    }
    ci_info "## END OF BUILD ##"
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>]"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    # And... go!
    ci_init_build
    ci_trace_build
    [[ $# -eq 0 ]] || {
        echo >&2 "error: unexpected argument: '$1'"
        echo >&2 "note: this program accepts environment options only"
        usage 2
    }
    ci_cleanup_old_build
    ci_build
 }
 main "$@"
--- a/ci/ci_verify_makefiles.sh
+++ b/ci/ci_verify_makefiles.sh
@ -1,200 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/lib/ci.lib.sh"
 cd "$CI_TOPLEVEL_DIR"
 CI_SRC_DIR="$CI_TOPLEVEL_DIR"
 function ci_init_build {
    # Ensure that the mandatory variables are initialized.
    CI_MAKE="${CI_MAKE:-make}"
    case "$CI_CC" in
    ( *clang* )
        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.clang"}" ;;
    ( *gcc* )
        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.gcc"}" ;;
    ( * )
        CI_MAKEFILES="${CI_MAKEFILES:-"scripts/makefile.std"}" ;;
    esac
 }
 function ci_trace_build {
    ci_info "## START OF CONFIGURATION ##"
    ci_info "build arch: $CI_BUILD_ARCH"
    ci_info "build system: $CI_BUILD_SYSTEM"
    [[ "$CI_TARGET_SYSTEM.$CI_TARGET_ARCH" != "$CI_BUILD_SYSTEM.$CI_BUILD_ARCH" ]] && {
        ci_info "target arch: $CI_TARGET_ARCH"
        ci_info "target system: $CI_TARGET_SYSTEM"
    }
    ci_info "source directory: $CI_SRC_DIR"
    ci_info "environment option: \$CI_MAKEFILES: '$CI_MAKEFILES'"
    ci_info "environment option: \$CI_MAKE: '$CI_MAKE'"
    ci_info "environment option: \$CI_MAKE_FLAGS: '$CI_MAKE_FLAGS'"
    ci_info "environment option: \$CI_MAKE_VARS: '$CI_MAKE_VARS'"
    ci_info "environment option: \$CI_CC: '$CI_CC'"
    ci_info "environment option: \$CI_CC_FLAGS: '$CI_CC_FLAGS'"
    ci_info "environment option: \$CI_CPP: '$CI_CPP'"
    ci_info "environment option: \$CI_CPP_FLAGS: '$CI_CPP_FLAGS'"
    ci_info "environment option: \$CI_AR: '$CI_AR'"
    ci_info "environment option: \$CI_RANLIB: '$CI_RANLIB'"
    ci_info "environment option: \$CI_LD: '$CI_LD'"
    ci_info "environment option: \$CI_LD_FLAGS: '$CI_LD_FLAGS'"
    ci_info "environment option: \$CI_LIBS: '$CI_LIBS'"
    ci_info "environment option: \$CI_SANITIZERS: '$CI_SANITIZERS'"
    ci_info "environment option: \$CI_FORCE: '$CI_FORCE'"
    ci_info "environment option: \$CI_NO_BUILD: '$CI_NO_BUILD'"
    ci_info "environment option: \$CI_NO_TEST: '$CI_NO_TEST'"
    ci_info "environment option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
    ci_info "executable: \$CI_MAKE: $(command -V "$CI_MAKE")"
    [[ $CI_CC ]] && {
        ci_info "executable: \$CI_CC: $(command -V "$CI_CC")"
    }
    [[ $CI_CPP ]] && {
        ci_info "executable: \$CI_CPP: $(command -V "$CI_CPP")"
    }
    [[ $CI_AR ]] && {
        ci_info "executable: \$CI_AR: $(command -V "$CI_AR")"
    }
    [[ $CI_RANLIB ]] && {
        ci_info "executable: \$CI_RANLIB: $(command -V "$CI_RANLIB")"
    }
    [[ $CI_LD ]] && {
        ci_info "executable: \$CI_LD: $(command -V "$CI_LD")"
    }
    ci_info "## END OF CONFIGURATION ##"
 }
 function ci_cleanup_old_build {
    # Any old makefile-based build will most likely leave a mess
    # of object files behind if interrupted, e.g., via Ctrl+C.
    # There may be other files behind, depending on what makefile
    # had been used. We cannot easily enumerate all of those.
    # Fortunately, for a clean makefiles-based build, it should be
    # sufficient to remove the old object files only.
    ci_info "## START OF PRE-BUILD CLEANUP ##"
    local find_args=(-maxdepth 1 \( -iname "*.o" -o -iname "*.obj" \))
    [[ ! $(find "$CI_SRC_DIR" "${find_args[@]}" | head -n1) ]] || {
        ci_warn "unexpected build found in '$CI_SRC_DIR'"
        if ci_expr $((CI_FORCE))
        then
            # Delete the old build.
            local my_file
            find "$CI_SRC_DIR" "${find_args[@]}" |
                while IFS="" read -r my_file
                do
                    ci_spawn rm -fr "$my_file"
                done
            ci_info "## END OF PRE-BUILD CLEANUP ##"
        else
            # Alert the user, but do not delete their existing files,
            # and do not mess up their existing build.
            ci_info "hint: consider using the option \$CI_FORCE=1"
            ci_err "unable to continue"
        fi
    }
 }
 function ci_build {
    ci_info "## START OF BUILD ##"
    # Initialize and populate the local arrays.
    local all_make_flags=()
    local all_make_vars=()
    [[ $CI_MAKE_FLAGS ]] && {
        all_make_flags+=($CI_MAKE_FLAGS)
    }
    [[ $CI_CC ]] && {
        all_make_vars+=("CC=$CI_CC")
    }
    [[ $CI_CC_FLAGS || $CI_SANITIZERS ]] && {
        [[ $CI_SANITIZERS ]] && CI_CC_FLAGS="${CI_CC_FLAGS:-"-O2"} -fsanitize=$CI_SANITIZERS"
        all_make_vars+=("CFLAGS=$CI_CC_FLAGS")
    }
    [[ $CI_CPP ]] && {
        all_make_vars+=("CPP=$CI_CPP")
    }
    [[ $CI_CPP_FLAGS ]] && {
        all_make_vars+=("CPPFLAGS=$CI_CPP_FLAGS")
    }
    [[ $CI_AR ]] && {
        all_make_vars+=("AR=$CI_AR")
    }
    [[ $CI_RANLIB ]] && {
        all_make_vars+=("RANLIB=$CI_RANLIB")
    }
    [[ $CI_LD ]] && {
        all_make_vars+=("LD=$CI_LD")
    }
    [[ $CI_LD_FLAGS || $CI_SANITIZERS ]] && {
        [[ $CI_SANITIZERS ]] && CI_LD_FLAGS+="${CI_LD_FLAGS:+" "}-fsanitize=$CI_SANITIZERS"
        all_make_vars+=("LDFLAGS=$CI_LD_FLAGS")
    }
    [[ $CI_LIBS ]] && {
        all_make_vars+=("LIBS=$CI_LIBS")
    }
    all_make_vars+=($CI_MAKE_VARS)
    # And... build!
    local my_makefile
    for my_makefile in $CI_MAKEFILES
    do
        ci_info "using makefile: $my_makefile"
        ci_expr $((CI_NO_BUILD)) || {
            # Spawn "make".
            ci_spawn "$CI_MAKE" -f "$my_makefile" \
                                "${all_make_flags[@]}" \
                                "${all_make_vars[@]}"
        }
        ci_expr $((CI_NO_TEST)) || {
            # Spawn "make test" if testing is not disabled.
            ci_spawn "$CI_MAKE" -f "$my_makefile" \
                                "${all_make_flags[@]}" \
                                "${all_make_vars[@]}" \
                                test
        }
        ci_expr $((CI_NO_CLEAN)) || {
            # Spawn "make clean" if cleaning is not disabled.
            ci_spawn "$CI_MAKE" -f "$my_makefile" \
                                "${all_make_flags[@]}" \
                                "${all_make_vars[@]}" \
                                clean
        }
    done
    ci_info "## END OF BUILD ##"
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>]"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    # And... go!
    ci_init_build
    ci_trace_build
    [[ $# -eq 0 ]] || {
        echo >&2 "error: unexpected argument: '$1'"
        echo >&2 "note: this program accepts environment options only"
        usage 2
    }
    ci_cleanup_old_build
    ci_build
 }
 main "$@"
--- a/ci/ci_verify_version.sh
+++ b/ci/ci_verify_version.sh
@ -1,191 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/lib/ci.lib.sh"
 cd "$CI_TOPLEVEL_DIR"
 # Declare the global environments collected from various sources.
 declare CI_ENV_LIBPNG_VER        # collected from png.h
 declare CI_ENV_AUTOCONF_VER      # collected from configure.ac
 declare CI_ENV_CMAKE_VER         # collected from CMakeLists.txt
 declare CI_ENV_LIBPNGCONFIG_VER  # collected from scripts/libpng-config-head.in
 function ci_run_shellify {
    local my_script my_result
    my_script="$CI_SCRIPT_DIR/libexec/ci_shellify_${1#--}.sh"
    shift 1
    [[ -f $my_script ]] || {
        ci_err_internal "missing script: '$my_script'"
    }
    ci_info "shellifying:" "$@"
    "$BASH" "$my_script" "$@"
    echo "$my_result" | "$BASH" --posix || ci_err "bad shellify output"
    echo "$my_result"
 }
 function ci_init_version_verification {
    ci_info "## START OF VERIFICATION ##"
    CI_ENV_LIBPNG_VER="$(ci_run_shellify --c png.h)"
    echo "$CI_ENV_LIBPNG_VER"
    CI_ENV_AUTOCONF_VER="$(ci_run_shellify --autoconf configure.ac)"
    echo "$CI_ENV_AUTOCONF_VER"
    CI_ENV_CMAKE_VER="$(ci_run_shellify --cmake CMakeLists.txt)"
    echo "$CI_ENV_CMAKE_VER"
    CI_ENV_LIBPNGCONFIG_VER="$(ci_run_shellify --shell scripts/libpng-config-head.in)"
    echo "$CI_ENV_LIBPNGCONFIG_VER"
 }
 # shellcheck disable=SC2154
 function ci_do_version_verification {
    local my_expect
    ci_info "## VERIFYING: version definitions in 'png.h' ##"
    eval "$CI_ENV_LIBPNG_VER"
    my_expect="${PNG_LIBPNG_VER_MAJOR}.${PNG_LIBPNG_VER_MINOR}.${PNG_LIBPNG_VER_RELEASE}"
    if [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect"* ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER_STRING == $my_expect*"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER_STRING != $my_expect*"
    fi
    my_expect=$((PNG_LIBPNG_VER_MAJOR*10000 + PNG_LIBPNG_VER_MINOR*100 + PNG_LIBPNG_VER_RELEASE))
    if [[ "$PNG_LIBPNG_VER" == "$my_expect" ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER == $my_expect"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER != $my_expect"
    fi
    my_expect=$((PNG_LIBPNG_VER_MAJOR*10 + PNG_LIBPNG_VER_MINOR))
    if [[ "$PNG_LIBPNG_VER_SHAREDLIB" == "$my_expect" ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER_SHAREDLIB == $my_expect"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER_SHAREDLIB != $my_expect"
    fi
    if [[ "$PNG_LIBPNG_VER_SONUM" == "$my_expect" ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER_SONUM == $my_expect"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER_SONUM != $my_expect"
    fi
    if [[ "$PNG_LIBPNG_VER_DLLNUM" == "$my_expect" ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER_DLLNUM == $my_expect"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER_DLLNUM != $my_expect"
    fi
    if [[ "$PNG_LIBPNG_VER_BUILD" == [01] ]]
    then
        ci_info "matched: \$PNG_LIBPNG_VER_BUILD == [01]"
    else
        ci_err "mismatched: \$PNG_LIBPNG_VER_BUILD != [01]"
    fi
    ci_info "## VERIFYING: build definitions in 'png.h' ##"
    my_expect="${PNG_LIBPNG_VER_MAJOR}.${PNG_LIBPNG_VER_MINOR}.${PNG_LIBPNG_VER_RELEASE}"
    if [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect" ]]
    then
        if [[ $PNG_LIBPNG_VER_BUILD -eq 0 ]]
        then
            ci_info "matched: \$PNG_LIBPNG_VER_BUILD -eq 0"
        else
            ci_err "mismatched: \$PNG_LIBPNG_VER_BUILD -ne 0"
        fi
        if [[ $PNG_LIBPNG_BUILD_BASE_TYPE -eq $PNG_LIBPNG_BUILD_STABLE ]]
        then
            ci_info "matched: \$PNG_LIBPNG_BUILD_BASE_TYPE -eq \$PNG_LIBPNG_BUILD_STABLE"
        else
            ci_err "mismatched: \$PNG_LIBPNG_BUILD_BASE_TYPE -ne \$PNG_LIBPNG_BUILD_STABLE"
        fi
    elif [[ "$PNG_LIBPNG_VER_STRING" == "$my_expect".git ]]
    then
        if [[ $PNG_LIBPNG_VER_BUILD -ne 0 ]]
        then
            ci_info "matched: \$PNG_LIBPNG_VER_BUILD -ne 0"
        else
            ci_err "mismatched: \$PNG_LIBPNG_VER_BUILD -eq 0"
        fi
        if [[ $PNG_LIBPNG_BUILD_BASE_TYPE -ne $PNG_LIBPNG_BUILD_STABLE ]]
        then
            ci_info "matched: \$PNG_LIBPNG_BUILD_BASE_TYPE -ne \$PNG_LIBPNG_BUILD_STABLE"
        else
            ci_err "mismatched: \$PNG_LIBPNG_BUILD_BASE_TYPE -eq \$PNG_LIBPNG_BUILD_STABLE"
        fi
    else
        ci_err "unexpected: \$PNG_LIBPNG_VER_STRING == '$PNG_LIBPNG_VER_STRING'"
    fi
    ci_info "## VERIFYING: type definitions in 'png.h' ##"
    my_expect="$(echo "png_libpng_version_${PNG_LIBPNG_VER_STRING}" | tr . _)"
    ci_spawn grep -w -e "$my_expect" png.h
    ci_info "## VERIFYING: version definitions in 'configure.ac' ##"
    eval "$CI_ENV_AUTOCONF_VER"
    if [[ "$PNGLIB_VERSION" == "$PNG_LIBPNG_VER_STRING" ]]
    then
        ci_info "matched: \$PNGLIB_VERSION == \$PNG_LIBPNG_VER_STRING"
    else
        ci_err "mismatched: \$PNGLIB_VERSION != \$PNG_LIBPNG_VER_STRING"
    fi
    ci_info "## VERIFYING: version definitions in 'CMakeLists.txt' ##"
    eval "$CI_ENV_CMAKE_VER"
    if [[ "$PNGLIB_VERSION" == "$PNG_LIBPNG_VER_STRING" && "$PNGLIB_SUBREVISION" == 0 ]]
    then
        ci_info "matched: \$PNGLIB_VERSION == \$PNG_LIBPNG_VER_STRING"
        ci_info "matched: \$PNGLIB_SUBREVISION == 0"
    elif [[ "$PNGLIB_VERSION.$PNGLIB_SUBREVISION" == "$PNG_LIBPNG_VER_STRING" ]]
    then
        ci_info "matched: \$PNGLIB_VERSION.\$PNGLIB_SUBREVISION == \$PNG_LIBPNG_VER_STRING"
    else
        ci_err "mismatched: \$PNGLIB_VERSION != \$PNG_LIBPNG_VER_STRING"
    fi
    ci_info "## VERIFYING: version definitions in 'scripts/libpng-config-head.in' ##"
    eval "$CI_ENV_LIBPNGCONFIG_VER"
    if [[ "$version" == "$PNG_LIBPNG_VER_STRING" ]]
    then
        ci_info "matched: \$version == \$PNG_LIBPNG_VER_STRING"
    else
        ci_err "mismatched: \$version != \$PNG_LIBPNG_VER_STRING"
    fi
 }
 function ci_finish_version_verification {
    ci_info "## END OF VERIFICATION ##"
    # Relying on "set -o errexit" to not reach here in case of error.
    ci_info "## SUCCESS ##"
 }
 function ci_verify_version {
    ci_init_version_verification
    ci_do_version_verification
    ci_finish_version_verification
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>]"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] || {
        echo >&2 "error: unexpected argument: '$1'"
        usage 2
    }
    # And... go!
    ci_verify_version
 }
 main "$@"
--- a/ci/lib/ci.lib.sh
+++ b/ci/lib/ci.lib.sh
@ -1,111 +0,0 @@
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 test -f "$BASH_SOURCE" || {
    echo >&2 "warning: this module requires Bash version 3 or newer"
 }
 test "${#BASH_SOURCE[@]}" -gt 1 || {
    echo >&2 "warning: this module should be sourced from a Bash script"
 }
 # Reset the locale to avoid surprises from locale-dependent commands.
 export LC_ALL=C
 export LANG=C
 export LANGUAGE=C
 # Reset CDPATH to avoid surprises from the "cd" command.
 export CDPATH=""
 # Initialize the global constants CI_SCRIPT_{NAME,DIR} and CI_TOPLEVEL_DIR.
 CI_SCRIPT_NAME="$(basename -- "$0")"
 CI_SCRIPT_DIR="$(cd "$(dirname -- "$0")" && pwd)"
 CI_TOPLEVEL_DIR="$(cd "$(dirname -- "${BASH_SOURCE[0]}")/../.." && pwd)"
 # Initialize the global constants CI_BUILD_{...} for the host build platform.
 CI_BUILD_ARCH="${CI_BUILD_ARCH:-"$(uname -m | tr 'A-Z/\.-' 'a-z____')"}"
 CI_BUILD_SYSTEM="${CI_BUILD_SYSTEM:-"$(uname -s | tr 'A-Z/\.-' 'a-z____')"}"
 # Initialize the global constants CI_TARGET_{...} for the target platform.
 CI_TARGET_ARCH="${CI_TARGET_ARCH:-"$CI_BUILD_ARCH"}"
 CI_TARGET_SYSTEM="${CI_TARGET_SYSTEM:-"$CI_BUILD_SYSTEM"}"
 function ci_info {
    printf >&2 "%s: %s\\n" "$CI_SCRIPT_NAME" "$*"
 }
 function ci_warn {
    printf >&2 "%s: warning: %s\\n" "$CI_SCRIPT_NAME" "$*"
 }
 function ci_err {
    printf >&2 "%s: error: %s\\n" "$CI_SCRIPT_NAME" "$*"
    exit 2
 }
 function ci_err_internal {
    printf >&2 "%s: internal error: %s\\n" "$CI_SCRIPT_NAME" "$*"
    printf >&2 "ABORTED\\n"
    # Exit with the conventional SIGABRT code.
    exit 134
 }
 function ci_expr {
    if [[ ${*:-0} == [0-9] ]]
    then
        # This is the same as in the else-branch below, albeit much faster
        # for our intended use cases.
        return $((!$1))
    else
        # The funny-looking compound command "... && return $? || return $?"
        # allows the execution to continue uninterrupted under "set -e".
        expr >/dev/null "$@" && return $? || return $?
    fi
 }
 function ci_spawn {
    printf >&2 "%s: executing:" "$CI_SCRIPT_NAME"
    printf >&2 " %q" "$@"
    printf >&2 "\\n"
    "$@"
 }
 # Ensure that the internal initialization is correct.
 [[ $CI_TOPLEVEL_DIR/ci/lib/ci.lib.sh -ef ${BASH_SOURCE[0]} ]] || {
    ci_err_internal "bad or missing \$CI_TOPLEVEL_DIR"
 }
 [[ $CI_SCRIPT_DIR/$CI_SCRIPT_NAME -ef $0 ]] || {
    ci_err_internal "bad or missing \$CI_SCRIPT_DIR/\$CI_SCRIPT_NAME"
 }
 [[ $CI_BUILD_ARCH && $CI_BUILD_SYSTEM ]] || {
    ci_err_internal "missing \$CI_BUILD_ARCH or \$CI_BUILD_SYSTEM"
 }
 [[ $CI_TARGET_ARCH && $CI_TARGET_SYSTEM ]] || {
    ci_err_internal "missing \$CI_TARGET_ARCH or \$CI_TARGET_SYSTEM"
 }
 # Ensure that the user initialization is correct.
 [[ ${CI_FORCE:-0} == [01] ]] || {
    ci_err "bad boolean option: \$CI_FORCE: '$CI_FORCE'"
 }
 [[ ${CI_NO_BUILD:-0} == [01] ]] || {
    ci_err "bad boolean option: \$CI_NO_BUILD: '$CI_NO_BUILD'"
 }
 [[ ${CI_NO_TEST:-0} == [01] ]] || {
    ci_err "bad boolean option: \$CI_NO_TEST: '$CI_NO_TEST'"
 }
 [[ ${CI_NO_INSTALL:-0} == [01] ]] || {
    ci_err "bad boolean option: \$CI_NO_INSTALL: '$CI_NO_INSTALL'"
 }
 [[ ${CI_NO_CLEAN:-0} == [01] ]] || {
    ci_err "bad boolean option: \$CI_NO_CLEAN: '$CI_NO_CLEAN'"
 }
 if ci_expr $((CI_NO_BUILD))
 then
    ci_expr $((CI_NO_TEST && CI_NO_INSTALL)) || {
        ci_err "\$CI_NO_BUILD requires \$CI_NO_TEST and \$CI_NO_INSTALL"
    }
 fi
--- a/ci/libexec/ci_shellify_autoconf.sh
+++ b/ci/libexec/ci_shellify_autoconf.sh
@ -1,48 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/../lib/ci.lib.sh"
 function ci_shellify_autoconf {
    # Convert autoconf (M4) text, specifically originating
    # from configure.ac, to shell scripting text.
    # Select only the easy-to-parse definitions of PNGLIB_*.
    sed -n -e '/^ *PNGLIB_[^ ]*=[$"0-9A-Za-z_]/ p' |
        sed -e 's/^ *PNG\([0-9A-Za-z_]*\)=\([^# ]*\).*$/PNG\1=\2/' \
            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>] configure.ac"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] && usage 2
    [[ $# -eq 1 ]] || ci_err "too many operands"
    # And... go!
    test -e "$1" || ci_err "no such file: '$1'"
    [[ $(basename -- "$1") == configure.ac ]] || {
        ci_err "incorrect operand: '$1' (expecting: 'configure.ac')"
    }
    ci_shellify_autoconf <"$1"
 }
 main "$@"
--- a/ci/libexec/ci_shellify_c.sh
+++ b/ci/libexec/ci_shellify_c.sh
@ -1,49 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/../lib/ci.lib.sh"
 function ci_shellify_c {
    # Convert C preprocessor text, specifically originating
    # from png.h, to shell scripting text.
    # Select only the easy-to-parse definitions of PNG_LIBPNG_*.
    sed -n -e '/^\# *define * PNG_LIBPNG_[^ ]* * ["0-9A-Za-z_]/ p' |
        sed -e 's/^\# *define * PNG\([^ ]*\) * \([^ ]*\)/PNG\1=\2/' \
            -e 's/=PNG\([0-9A-Za-z_]*\)/=\${PNG\1}/' \
            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>] png.h"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] && usage 2
    [[ $# -eq 1 ]] || ci_err "too many operands"
    # And... go!
    test -e "$1" || ci_err "no such file: '$1'"
    [[ $(basename -- "$1") == png.h ]] || {
        ci_err "incorrect operand: '$1' (expecting: 'png.h')"
    }
    ci_shellify_c <"$1"
 }
 main "$@"
--- a/ci/libexec/ci_shellify_cmake.sh
+++ b/ci/libexec/ci_shellify_cmake.sh
@ -1,49 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/../lib/ci.lib.sh"
 function ci_shellify_cmake {
    # Convert CMake lists text, specifically originating
    # from CMakeLists.txt, to shell scripting text.
    # Select only the easy-to-parse definitions of PNGLIB_*.
    sed -n -e '/^ *set *(PNGLIB_[^ ]* * [$"0-9A-Za-z_].*)/ p' |
        sed -e 's/^ *set *(PNG\([^ ]*\) * \([^() ]*\)).*$/PNG\1=\2/' \
            -e 's/^\([^ ]*=[^ ]*\).*$/export \1;/'
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>] CMakeLists.txt"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] && usage 2
    [[ $# -eq 1 ]] || ci_err "too many operands"
    # And... go!
    test -e "$1" || ci_err "no such file: '$1'"
    filename="$(basename -- "$1")"
    [[ $filename == [Cc][Mm]ake[Ll]ists.txt ]] || {
        ci_err "incorrect operand: '$1' (expecting: 'CMakeLists.txt')"
    }
    ci_shellify_cmake <"$1"
 }
 main "$@"
--- a/ci/libexec/ci_shellify_shell.sh
+++ b/ci/libexec/ci_shellify_shell.sh
@ -1,46 +0,0 @@
 #!/usr/bin/env bash
 set -o errexit -o pipefail -o posix
 # Copyright (c) 2019-2025 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 # shellcheck source=ci/lib/ci.lib.sh
 source "$(dirname "$0")/../lib/ci.lib.sh"
 function ci_shellify_shell {
    # Convert shell scripting text to shell scripting text.
    # Select only the easy-to-parse version definitions.
    sed -n -e '/^ *[A-Za-z_][0-9A-Za-z_]*=[0-9][^ #]* *$/ p' |
        sed -e 's/^ *\([^ ]*=[^ ]*\) *$/export \1;/'
 }
 function usage {
    echo "usage: $CI_SCRIPT_NAME [<options>] libpng-config-head.in"
    echo "options: -?|-h|--help"
    exit "${@:-0}"
 }
 function main {
    local opt
    while getopts ":" opt
    do
        # This ain't a while-loop. It only pretends to be.
        [[ $1 == -[?h]* || $1 == --help || $1 == --help=* ]] && usage 0
        ci_err "unknown option: '$1'"
    done
    shift $((OPTIND - 1))
    [[ $# -eq 0 ]] && usage 2
    [[ $# -eq 1 ]] || ci_err "too many operands"
    # And... go!
    test -e "$1" || ci_err "no such file: '$1'"
    [[ $(basename -- "$1") == libpng-config-head.in ]] || {
        ci_err "incorrect operand: '$1' (expecting: 'libpng-config-head.in')"
    }
    ci_shellify_shell <"$1"
 }
 main "$@"
--- a/ci/targets/android/ci_env.aarch64-linux-android.sh
+++ b/ci/targets/android/ci_env.aarch64-linux-android.sh
@ -1,16 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=aarch64
 export CI_TARGET_ARCHVER=aarch64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=android
 export CI_TARGET_ABIVER=android29
 export CI_CC="$CI_TARGET_ARCHVER-$CI_TARGET_SYSTEM-$CI_TARGET_ABIVER-clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
--- a/ci/targets/android/ci_env.armv7a-linux-androideabi.sh
+++ b/ci/targets/android/ci_env.armv7a-linux-androideabi.sh
@ -1,16 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=arm
 export CI_TARGET_ARCHVER=armv7a
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=androideabi
 export CI_TARGET_ABIVER=androideabi29
 export CI_CC="$CI_TARGET_ARCHVER-$CI_TARGET_SYSTEM-$CI_TARGET_ABIVER-clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
--- a/ci/targets/android/ci_env.i686-linux-android.sh
+++ b/ci/targets/android/ci_env.i686-linux-android.sh
@ -1,16 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_ARCHVER=i686
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=android
 export CI_TARGET_ABIVER=android29
 export CI_CC="$CI_TARGET_ARCHVER-$CI_TARGET_SYSTEM-$CI_TARGET_ABIVER-clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
--- a/ci/targets/android/ci_env.x86_64-linux-android.sh
+++ b/ci/targets/android/ci_env.x86_64-linux-android.sh
@ -1,16 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_ARCHVER=x86_64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=android
 export CI_TARGET_ABIVER=android29
 export CI_CC="$CI_TARGET_ARCHVER-$CI_TARGET_SYSTEM-$CI_TARGET_ABIVER-clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
--- a/ci/targets/cygwin/ci_env.i686-pc-cygwin.sh
+++ b/ci/targets/cygwin/ci_env.i686-pc-cygwin.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_SYSTEM=cygwin
 export CI_CC="$CI_TARGET_ARCH-pc-$CI_TARGET_SYSTEM-gcc"
 export CI_AR="$CI_CC-ar"
 export CI_RANLIB="$CI_CC-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=CYGWIN
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/cygwin/ci_env.x86_64-pc-cygwin.sh
+++ b/ci/targets/cygwin/ci_env.x86_64-pc-cygwin.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=cygwin
 export CI_CC="$CI_TARGET_ARCH-pc-$CI_TARGET_SYSTEM-gcc"
 export CI_AR="$CI_CC-ar"
 export CI_RANLIB="$CI_CC-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=CYGWIN
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/darwin/ci_env.arm64-apple-darwin.sh
+++ b/ci/targets/darwin/ci_env.arm64-apple-darwin.sh
@ -1,15 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=arm64
 export CI_TARGET_SYSTEM=darwin
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Darwin
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
    -DCMAKE_OSX_ARCHITECTURES=$CI_TARGET_ARCH
 "
--- a/ci/targets/darwin/ci_env.x86_64-apple-darwin.sh
+++ b/ci/targets/darwin/ci_env.x86_64-apple-darwin.sh
@ -1,15 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=darwin
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Darwin
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
    -DCMAKE_OSX_ARCHITECTURES=$CI_TARGET_ARCH
 "
--- a/ci/targets/freebsd/ci_env.aarch64-unknown-freebsd.sh
+++ b/ci/targets/freebsd/ci_env.aarch64-unknown-freebsd.sh
@ -1,14 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=aarch64
 export CI_TARGET_SYSTEM=freebsd
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=FreeBSD
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/freebsd/ci_env.i686-unknown-freebsd.sh
+++ b/ci/targets/freebsd/ci_env.i686-unknown-freebsd.sh
@ -1,14 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_SYSTEM=freebsd
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=FreeBSD
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/freebsd/ci_env.riscv64-unknown-freebsd.sh
+++ b/ci/targets/freebsd/ci_env.riscv64-unknown-freebsd.sh
@ -1,14 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=riscv64
 export CI_TARGET_SYSTEM=freebsd
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=FreeBSD
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/freebsd/ci_env.x86_64-unknown-freebsd.sh
+++ b/ci/targets/freebsd/ci_env.x86_64-unknown-freebsd.sh
@ -1,14 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=freebsd
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=FreeBSD
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.aarch64-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.aarch64-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=aarch64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.arm-linux-gnueabi.sh
+++ b/ci/targets/linux/ci_env.arm-linux-gnueabi.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=arm
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnueabi
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.arm-linux-gnueabihf.sh
+++ b/ci/targets/linux/ci_env.arm-linux-gnueabihf.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=arm
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnueabihf
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.i686-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.i686-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mips-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.mips-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mips
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mips64-linux-gnuabi64.sh
+++ b/ci/targets/linux/ci_env.mips64-linux-gnuabi64.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mips64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnuabi64
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mips64el-linux-gnuabi64.sh
+++ b/ci/targets/linux/ci_env.mips64el-linux-gnuabi64.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mips64el
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnuabi64
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mipsel-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.mipsel-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mipsel
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mipsisa32r6-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.mipsisa32r6-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mipsisa32r6
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mipsisa32r6el-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.mipsisa32r6el-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mipsisa32r6el
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mipsisa64r6-linux-gnuabi64.sh
+++ b/ci/targets/linux/ci_env.mipsisa64r6-linux-gnuabi64.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mipsisa64r6
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnuabi64
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.mipsisa64r6el-linux-gnuabi64.sh
+++ b/ci/targets/linux/ci_env.mipsisa64r6el-linux-gnuabi64.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=mipsisa64r6el
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnuabi64
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.powerpc-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.powerpc-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=powerpc
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.powerpc64-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.powerpc64-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=powerpc64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.powerpc64le-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.powerpc64le-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=powerpc64le
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.riscv64-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.riscv64-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=riscv64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/linux/ci_env.x86_64-linux-gnu.sh
+++ b/ci/targets/linux/ci_env.x86_64-linux-gnu.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=linux
 export CI_TARGET_ABI=gnu
 export CI_GCC="${CI_GCC-gcc}"
 export CI_CC="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-$CI_GCC"
 export CI_AR="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ar"
 export CI_RANLIB="$CI_TARGET_ARCH-$CI_TARGET_SYSTEM-$CI_TARGET_ABI-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Linux
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/msdos/ci_env.i386-pc-msdoswatcom.sh
+++ b/ci/targets/msdos/ci_env.i386-pc-msdoswatcom.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i386
 export CI_TARGET_SYSTEM=msdoswatcom
 export CI_CC="wcl386"
 # Open Watcom V2 CMake build
 # https://github.com/open-watcom/open-watcom-v2/discussions/716
 export CI_CMAKE_GENERATOR="Watcom WMake"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=DOS
 "
--- a/ci/targets/msdos/ci_env.i586-pc-msdosdjgpp.sh
+++ b/ci/targets/msdos/ci_env.i586-pc-msdosdjgpp.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i586
 export CI_TARGET_SYSTEM=msdosdjgpp
 export CI_CC="$CI_TARGET_ARCH-pc-$CI_TARGET_SYSTEM-gcc"
 export CI_AR="$CI_CC-ar"
 export CI_RANLIB="$CI_CC-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Generic
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/msdos/ci_env.i86-pc-msdoswatcom.sh
+++ b/ci/targets/msdos/ci_env.i86-pc-msdoswatcom.sh
@ -1,19 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i86
 export CI_TARGET_SYSTEM=msdoswatcom
 export CI_CC="wcl"
 # Open Watcom V2 CMake build
 # https://github.com/open-watcom/open-watcom-v2/discussions/716
 export CI_CMAKE_GENERATOR="Watcom WMake"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=DOS
    -DCMAKE_SYSTEM_PROCESSOR=I86
 "
--- a/ci/targets/windows/ci_env.aarch64-windows-llvm.sh
+++ b/ci/targets/windows/ci_env.aarch64-windows-llvm.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=aarch64
 export CI_TARGET_SYSTEM=windows
 export CI_CC="clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Windows
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/windows/ci_env.i686-w64-mingw32.sh
+++ b/ci/targets/windows/ci_env.i686-w64-mingw32.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_SYSTEM=mingw32
 # The output of `uname -s` on MSYS2 is understandable, and so is
 # CI_TARGET_SYSTEM above, in simplified form. (See also Cygwin.)
 # But aside from that, the Mingw-w64 nomenclature is rather messy.
 export CI_CC="$CI_TARGET_ARCH-w64-mingw32-gcc"
 export CI_AR="$CI_CC-ar"
 export CI_RANLIB="$CI_CC-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Windows
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/windows/ci_env.i686-windows-llvm.sh
+++ b/ci/targets/windows/ci_env.i686-windows-llvm.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=i686
 export CI_TARGET_SYSTEM=windows
 export CI_CC="clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Windows
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/windows/ci_env.x86_64-w64-mingw32.sh
+++ b/ci/targets/windows/ci_env.x86_64-w64-mingw32.sh
@ -1,21 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=mingw64
 # The output of `uname -s` on MSYS2 is understandable, and so is
 # CI_TARGET_SYSTEM above, in simplified form. (See also Cygwin.)
 # But aside from that, the Mingw-w64 nomenclature is rather messy.
 export CI_CC="$CI_TARGET_ARCH-w64-mingw32-gcc"
 export CI_AR="$CI_CC-ar"
 export CI_RANLIB="$CI_CC-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Windows
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/ci/targets/windows/ci_env.x86_64-windows-llvm.sh
+++ b/ci/targets/windows/ci_env.x86_64-windows-llvm.sh
@ -1,18 +0,0 @@
 # Copyright (c) 2023-2024 Cosmin Truta.
 #
 # Use, modification and distribution are subject to the MIT License.
 # Please see the accompanying file LICENSE_MIT.txt
 #
 # SPDX-License-Identifier: MIT
 export CI_TARGET_ARCH=x86_64
 export CI_TARGET_SYSTEM=windows
 export CI_CC="clang"
 export CI_AR="llvm-ar"
 export CI_RANLIB="llvm-ranlib"
 export CI_CMAKE_VARS="
    -DCMAKE_SYSTEM_NAME=Windows
    -DCMAKE_SYSTEM_PROCESSOR=$CI_TARGET_ARCH
 "
--- a/38
+++ b/38
@ -1,9 +1,9 @@
 #! /bin/sh
 # Wrapper for compilers which do not understand '-c -o'.
-scriptversion=2025-06-18.21; # UTC
+scriptversion=2018-03-07.03; # UTC
-# Copyright (C) 1999-2025 Free Software Foundation, Inc.
+# Copyright (C) 1999-2018 Free Software Foundation, Inc.
 # Written by Tom Tromey <tromey@cygnus.com>.
 #
 # This program is free software; you can redistribute it and/or modify
@ -37,11 +37,11 @@ IFS=" ""	$nl"
 file_conv=
-# func_file_conv build_file unneeded_conversions
+# func_file_conv build_file lazy
 # Convert a $build file to $host form and store it in $file
 # Currently only supports Windows hosts. If the determined conversion
-# type is listed in (the comma separated) UNNEEDED_CONVERSIONS, no
+# type is listed in (the comma separated) LAZY, no conversion will
-# conversion will take place.
+# take place.
 func_file_conv ()
 {
  file=$1
@ -51,20 +51,9 @@ func_file_conv ()
 	# lazily determine how to convert abs files
 	case `uname -s` in
 	  MINGW*)
-	    if test -n "$MSYSTEM" && (cygpath --version) >/dev/null 2>&1; then
+	    file_conv=mingw
 	      # MSYS2 environment.
 	      file_conv=cygwin
 	    else
 	      # Original MinGW environment.
 	      file_conv=mingw
 	    fi
 	    ;;
 	  MSYS*)
 	    # Old MSYS environment, or MSYS2 with 32-bit MSYS2 shell.
 	    file_conv=cygwin
 	    ;;
 	  CYGWIN*)
 	    # Cygwin environment.
 	    file_conv=cygwin
 	    ;;
 	  *)
@ -74,14 +63,12 @@ func_file_conv ()
      fi
      case $file_conv/,$2, in
 	*,$file_conv,*)
 	  # This is the optimization mentioned above:
 	  # If UNNEEDED_CONVERSIONS contains $file_conv, don't convert.
 	  ;;
 	mingw/*)
 	  file=`cmd //C echo "$file " | sed -e 's/"\(.*\) " *$/\1/'`
 	  ;;
 	cygwin/*)
-	  file=`cygpath -w "$file" || echo "$file"`
+	  file=`cygpath -m "$file" || echo "$file"`
 	  ;;
 	wine/*)
 	  file=`winepath -w "$file" || echo "$file"`
@ -156,7 +143,7 @@ func_cl_wrapper ()
 	  # configure might choose to run compile as 'compile cc -o foo foo.c'.
 	  eat=1
 	  case $2 in
-	    *.o | *.lo | *.[oO][bB][jJ])
+	    *.o | *.[oO][bB][jJ])
 	      func_file_conv "$2"
 	      set x "$@" -Fo"$file"
 	      shift
@ -261,17 +248,14 @@ If you are trying to build a whole package this is not the
 right script to run: please start by reading the file 'INSTALL'.
 Report bugs to <bug-automake@gnu.org>.
 GNU Automake home page: <https://www.gnu.org/software/automake/>.
 General help using GNU software: <https://www.gnu.org/gethelp/>.
 EOF
    exit $?
    ;;
  -v | --v*)
-    echo "compile (GNU Automake) $scriptversion"
+    echo "compile $scriptversion"
    exit $?
    ;;
  cl | *[/\\]cl | cl.exe | *[/\\]cl.exe | \
  clang-cl | *[/\\]clang-cl | clang-cl.exe | *[/\\]clang-cl.exe | \
  icl | *[/\\]icl | icl.exe | *[/\\]icl.exe )
    func_cl_wrapper "$@"      # Doesn't return...
    ;;
@ -356,9 +340,9 @@ exit $ret
 # Local Variables:
 # mode: shell-script
 # sh-indentation: 2
-# eval: (add-hook 'before-save-hook 'time-stamp nil t)
+# eval: (add-hook 'before-save-hook 'time-stamp)
 # time-stamp-start: "scriptversion="
-# time-stamp-format: "%Y-%02m-%02d.%02H"
+# time-stamp-format: "%:y-%02m-%02d.%02H"
 # time-stamp-time-zone: "UTC0"
 # time-stamp-end: "; # UTC"
 # End:
--- a/config.guess
+++ b/config.guess
--- a/config.h.in
+++ b/config.h.in
@ -3,27 +3,27 @@
 /* Define to 1 if you have the <dlfcn.h> header file. */
 #undef HAVE_DLFCN_H
-/* Define to 1 if you have the 'feenableexcept' function. */
+/* Define to 1 if you have the `feenableexcept' function. */
 #undef HAVE_FEENABLEEXCEPT
 /* Define to 1 if you have the <inttypes.h> header file. */
 #undef HAVE_INTTYPES_H
-/* Define to 1 if you have the 'm' library (-lm). */
+/* Define to 1 if you have the `m' library (-lm). */
 #undef HAVE_LIBM
-/* Define to 1 if you have the 'z' library (-lz). */
+/* Define to 1 if you have the `z' library (-lz). */
 #undef HAVE_LIBZ
-/* Define to 1 if you have the 'pow' function. */
+/* Define to 1 if you have the <memory.h> header file. */
 #undef HAVE_MEMORY_H
 /* Define to 1 if you have the `pow' function. */
 #undef HAVE_POW
 /* Define to 1 if you have the <stdint.h> header file. */
 #undef HAVE_STDINT_H
 /* Define to 1 if you have the <stdio.h> header file. */
 #undef HAVE_STDIO_H
 /* Define to 1 if you have the <stdlib.h> header file. */
 #undef HAVE_STDLIB_H
@ -78,18 +78,6 @@
 /* Enable Intel SSE optimizations */
 #undef PNG_INTEL_SSE_OPT
 /* Enable LOONGARCH LSX optimizations */
 #undef PNG_LOONGARCH_LSX_OPT
 /* Turn on MIPS MMI optimizations at run-time */
 #undef PNG_MIPS_MMI_API_SUPPORTED
 /* Check for MIPS MMI support at run-time */
 #undef PNG_MIPS_MMI_CHECK_SUPPORTED
 /* Enable MIPS MMI optimizations */
 #undef PNG_MIPS_MMI_OPT
 /* Turn on MIPS MSA optimizations at run-time */
 #undef PNG_MIPS_MSA_API_SUPPORTED
@ -108,31 +96,31 @@
 /* Enable POWERPC VSX optimizations */
 #undef PNG_POWERPC_VSX_OPT
-/* Enable RISCV RVV optimizations */
+/* Define to 1 if you have the ANSI C header files. */
 #undef PNG_RISCV_RVV_OPT
 /* Define to 1 if all of the C89 standard headers exist (not just the ones
   required in a freestanding environment). This macro is provided for
   backward compatibility; new code need not use it. */
 #undef STDC_HEADERS
-/* Define to 1 if your <sys/time.h> declares 'struct tm'. */
+/* Define to 1 if your <sys/time.h> declares `struct tm'. */
 #undef TM_IN_SYS_TIME
 /* Version number of package */
 #undef VERSION
 /* Define to empty if `const' does not conform to ANSI C. */
 #undef const
 /* Define to the equivalent of the C99 'restrict' keyword, or to
   nothing if this is not supported.  Do not define if restrict is
-   supported only directly.  */
+   supported directly.  */
 #undef restrict
-/* Work around a bug in older versions of Sun C++, which did not
+/* Work around a bug in Sun C++: it does not support _Restrict or
-   #define __restrict__ or support _Restrict or __restrict__
+   __restrict__, even though the corresponding Sun C compiler ends up with
-   even though the corresponding Sun C compiler ended up with
+   "#define restrict _Restrict" or "#define restrict __restrict__" in the
-   "#define restrict _Restrict" or "#define restrict __restrict__"
+   previous line.  Perhaps some future version of Sun C++ will work with
-   in the previous line.  This workaround can be removed once
+   restrict; if so, hopefully it defines __RESTRICT like Sun C does.  */
-   we assume Oracle Developer Studio 12.5 (2016) or later.  */
+#if defined __SUNPRO_CC && !defined __RESTRICT
 #if defined __SUNPRO_CC && !defined __RESTRICT && !defined __restrict__
 # define _Restrict
 # define __restrict__
 #endif
 /* Define to `unsigned int' if <sys/types.h> does not define. */
 #undef size_t
--- a/config.sub
+++ b/config.sub
--- a/8829
+++ b/8829
--- a/configure.ac
+++ b/configure.ac
@ -1,6 +1,6 @@
 # configure.ac
-# Copyright (c) 2018-2024 Cosmin Truta
+# Copyright (c) 2018 Cosmin Truta
 # Copyright (c) 2004-2016 Glenn Randers-Pehrson
 # This code is released under the libpng license.
@ -25,8 +25,8 @@ AC_PREREQ([2.68])
 dnl Version number stuff here:
-AC_INIT([libpng],[1.6.51.git],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.37],[png-mng-implement@lists.sourceforge.net])
-AC_CONFIG_MACRO_DIR([scripts/autoconf])
+AC_CONFIG_MACRO_DIR([scripts])
 # libpng does not follow GNU file name conventions (hence 'foreign')
 # color-tests requires automake 1.11 or later
@ -46,17 +46,17 @@ dnl automake, so the following is not necessary (and is not defined anyway):
 dnl AM_PREREQ([1.11.2])
 dnl stop configure from automagically running automake
-PNGLIB_VERSION=1.6.51.git
+PNGLIB_VERSION=1.6.37
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=51
+PNGLIB_RELEASE=37
 dnl End of version number stuff
 AC_CONFIG_SRCDIR([pngget.c])
 AC_CONFIG_HEADERS([config.h])
-# Check the basic programs.
+# Checks for programs.
 AC_LANG([C])
 AC_PROG_CC
 AM_PROG_AS
@ -72,19 +72,16 @@ dnl compatible later version may be used
 LT_INIT([win32-dll])
 LT_PREREQ([2.4.2])
-dnl Declare the AWK variable.
+# Some awks crash when confronted with pnglibconf.dfa, do a test run now
-AC_ARG_VAR(AWK, [AWK language processor])
+# to make sure this doesn't happen
-
+AC_MSG_CHECKING([that AWK works])
 # Some awk implementations crash when confronted with pnglibconf.dfa.
 # Run a test now, to make sure this doesn't happen.
 AC_MSG_CHECKING([if awk ($AWK) works])
 if ${AWK} -f ${srcdir}/scripts/options.awk out="/dev/null" version=search\
   ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
   ${srcdir}/pngusr.dfa 1>&2
 then
-   AC_MSG_RESULT([yes])
+   AC_MSG_RESULT([ok])
 else
-   AC_MSG_FAILURE([no], 1)
+   AC_MSG_FAILURE([failed], 1)
 fi
 # This is a remnant of the old cc -E validation, where it may have been
@ -92,29 +89,11 @@ fi
 DFNCPP="$CPP"
 AC_SUBST(DFNCPP)
-AC_ARG_ENABLE([tests],
+# -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
-   AS_HELP_STRING([--disable-tests],
+# checks the compiler with a program that generates a warning), add the
-      [do not build the test programs (default is to build)]),
+# following option to deal with this
      [enable_tests="$enableval"],
      [enable_tests=yes])
 AM_CONDITIONAL([ENABLE_TESTS],
   [test "$enable_tests" != "no"])
 AC_ARG_ENABLE([tools],
   AS_HELP_STRING([--disable-tools],
      [do not build the auxiliary tools (default is to build)]),
      [enable_tools="$enableval"],
      [enable_tools=yes])
 AM_CONDITIONAL([ENABLE_TOOLS],
   [test "$enable_tools" != "no"])
 # -Werror cannot be passed to GCC in CFLAGS because configure will fail
 # (it checks the compiler with a program that generates a warning).
 # Add the following option to deal with this:
 AC_ARG_VAR(PNG_COPTS,
-   [additional flags for the C compiler, to be used for options that would]
+   [additional flags for the C compiler, use this for options that would]
   [cause configure itself to fail])
 AC_ARG_ENABLE(werror,
   AS_HELP_STRING([[[--enable-werror[=OPT]]]],
@ -135,10 +114,10 @@ AC_ARG_ENABLE(werror,
      CFLAGS="$sav_CFLAGS"
    fi],)
-# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89.
+# For GCC 5 the default mode for C is -std=gnu11 instead of -std=gnu89
-# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining
+# In pngpriv.h we request just the POSIX 1003.1 and C89 APIs by defining _POSIX_SOURCE to 1
-# _POSIX_SOURCE to 1. This is incompatible with the new default mode, so
+# This is incompatible with the new default mode, so we test for that and force the 
-# we test for that and force the "-std=c89" compiler option:
+# "-std=c89" compiler option:
 AC_MSG_CHECKING([if we need to force back C standard to C89])
 AC_COMPILE_IFELSE(
   [AC_LANG_PROGRAM([
@ -154,17 +133,22 @@ AC_COMPILE_IFELSE(
   CFLAGS="$CFLAGS -std=c89"
 ])
-# Checks for structures and compiler characteristics.
+# Checks for header files.
 AC_HEADER_STDC
 # Checks for typedefs, structures, and compiler characteristics.
 AC_C_CONST
 AC_TYPE_SIZE_T
 AC_STRUCT_TM
 AC_C_RESTRICT
 # Checks for library functions.
-AC_CHECK_FUNCS([pow], ,
+AC_FUNC_STRTOD
-  [AC_CHECK_LIB([m], [pow], , [AC_MSG_ERROR([cannot find pow])])])
+AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
-# Some later POSIX 1003.1 functions are required for test programs, failure
+# Some later POSIX 1003.1 functions are required for test programs, failure here
-# here is soft (the corresponding test program is not built).
+# is soft (the corresponding test program is not built).
-AC_CHECK_FUNC([clock_gettime], , [AC_MSG_WARN([not building timepng])])
+AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
 AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
 AC_ARG_WITH(zlib-prefix,
@ -172,9 +156,8 @@ AC_ARG_WITH(zlib-prefix,
      [prefix that may have been used in installed zlib]),
      [ZPREFIX=${withval}],
      [ZPREFIX='z_'])
-AC_CHECK_LIB([z], [zlibVersion], ,
+AC_CHECK_LIB(z, zlibVersion, ,
-  [AC_CHECK_LIB([z], [${ZPREFIX}zlibVersion], ,
+    AC_CHECK_LIB(z, ${ZPREFIX}zlibVersion, , AC_MSG_ERROR(zlib not installed)))
     [AC_MSG_ERROR([zlib not installed])])])
 # The following is for pngvalid, to ensure it catches FP errors even on
 # platforms that don't enable FP exceptions, the function appears in the math
@ -226,9 +209,9 @@ AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
 if test "$have_ld_version_script" = "yes"; then
    AC_MSG_CHECKING([for symbol prefix])
    SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
-                  | ${CPP:-${CC:-gcc} -E} - 2>&1 \
+                  | ${CPP-${CC-gcc} -E} - 2>&1 \
-                  | ${EGREP:-grep} "^PREFIX=" \
+                  | ${EGREP-grep} "^PREFIX=" \
-                  | ${SED:-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
+                  | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
    AC_SUBST(SYMBOL_PREFIX)
    AC_MSG_RESULT($SYMBOL_PREFIX)
 fi
@ -313,7 +296,7 @@ AC_ARG_ENABLE([unversioned-libpng-config],
 AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
   [test "$enable_unversioned_libpng_config" != "no"])
-# HOST-SPECIFIC OPTIONS
+# HOST SPECIFIC OPTIONS
 # =====================
 #
 # DEFAULT
@ -321,7 +304,7 @@ AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
 #
 AC_ARG_ENABLE([hardware-optimizations],
   AS_HELP_STRING([[[--enable-hardware-optimizations]]],
-      [Enable hardware optimizations: =no/off, yes/on.]),
+      [Enable hardware optimizations: =no/off, yes/on:]),
   [case "$enableval" in
      no|off)
         # disable hardware optimization on all systems:
@ -331,36 +314,24 @@ AC_ARG_ENABLE([hardware-optimizations],
         enable_mips_msa=no
         AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
           [Disable MIPS_MSA optimizations])
         enable_mips_mmi=no
         AC_DEFINE([PNG_MIPS_MMI_OPT], [0],
           [Disable MIPS_MMI optimizations])
         enable_powerpc_vsx=no
         AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
           [Disable POWERPC VSX optimizations])
         enable_intel_sse=no
         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
           [Disable INTEL_SSE optimizations])
         enable_loongarch_lsx=no
         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [0],
           [Disable LOONGARCH_LSX optimizations])
         enable_riscv_rvv=no
         AC_DEFINE([PNG_RISCV_RVV_OPT], [0],
           [Disable RISC-V Vector optimizations])
         ;;
      *)
         # allow enabling hardware optimization on any system:
         case "$host_cpu" in
            arm*|aarch64*)
              enable_arm_neon=yes
-              AC_DEFINE([PNG_ARM_NEON_OPT], [2],
+              AC_DEFINE([PNG_ARM_NEON_OPT], [0],
                [Enable ARM_NEON optimizations])
              ;;
            mipsel*|mips64el*)
              enable_mips_mmi=yes
              enable_mips_msa=yes
-              AC_DEFINE([PNG_MIPS_MMI_OPT], [1],
+              AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
                [Enable MIPS_MMI optimizations])
              AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
                [Enable MIPS_MSA optimizations])
              ;;
            i?86|x86_64)
@ -373,30 +344,21 @@ AC_ARG_ENABLE([hardware-optimizations],
              AC_DEFINE([PNG_POWERPC_VSX_OPT], [2],
                [Enable POWERPC VSX optimizations])
              ;;
            loongarch*)
              enable_loongarch_lsx=yes
              AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1],
                [Enable LOONGARCH_LSX optimizations])
              ;;
            riscv64)
              enable_riscv_rvv=yes
              AC_DEFINE([PNG_RISCV_RVV_OPT], [2],
                [Enable RISC-V Vector optimizations])
              ;;
         esac
         ;;
   esac])
-# ARM NEON
+# ARM
-# ========
+# ===
 #
 # ARM NEON (SIMD) support.
 AC_ARG_ENABLE([arm-neon],
   AS_HELP_STRING([[[--enable-arm-neon]]],
-      [Enable ARM NEON optimizations: =no/off, check, api, yes/on.]
+      [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
-      [no/off: disable the optimizations;]
+      [no/off: disable the optimizations; check: use internal checking code]
-      [check: use internal checking code (deprecated and poorly supported);]
+      [(deprecated and poorly supported); api: disable by default, enable by]
-      [api: disable by default, enable by a call to png_set_option;]
+      [a call to png_set_option; yes/on: turn on unconditionally.]
      [yes/on: turn on unconditionally.]
      [If not specified: determined by the compiler.]),
   [case "$enableval" in
      no|off)
@ -404,7 +366,7 @@ AC_ARG_ENABLE([arm-neon],
         AC_DEFINE([PNG_ARM_NEON_OPT], [0],
                   [Disable ARM Neon optimizations])
         # Prevent inclusion of the assembler files below:
-         enable_arm_neon=no ;;
+         enable_arm_neon=no;;
      check)
         AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
                   [Check for ARM Neon support at run-time]);;
@ -414,35 +376,35 @@ AC_ARG_ENABLE([arm-neon],
      yes|on)
         AC_DEFINE([PNG_ARM_NEON_OPT], [2],
                   [Enable ARM Neon optimizations])
-         AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api';]
+         AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api', if]
-            [if you want the optimizations unconditionally,]
+            [you want the optimizations unconditionally pass -mfpu=neon]
-            [pass '-mfpu=neon' to the compiler.]);;
+            [to the compiler.]);;
      *)
-         AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}:]
+         AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
                      [invalid argument])
   esac])
-# Add ARM-specific files to all builds where $host_cpu is arm ('arm*') or
+# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
-# where ARM optimizations were explicitly requested. (This allows a fallback
+# where ARM optimizations were explicitly requested (this allows a fallback if a
-# if a future host CPU does not match 'arm*'.)
+# future host CPU does not match 'arm*')
 AM_CONDITIONAL([PNG_ARM_NEON],
   [test "$enable_arm_neon" != 'no' &&
    case "$host_cpu" in
-      arm*|aarch64*) : ;;
+      arm*|aarch64*) :;;
-      *)    test "$enable_arm_neon" != '' ;;
+      *)    test "$enable_arm_neon" != '';;
    esac])
-# MIPS MSA
+# MIPS
-# ========
+# ===
 #
 # MIPS MSA (SIMD) support.
 AC_ARG_ENABLE([mips-msa],
   AS_HELP_STRING([[[--enable-mips-msa]]],
-      [Enable MIPS MSA optimizations: =no/off, check, api, yes/on.]
+      [Enable MIPS MSA optimizations: =no/off, check, api, yes/on:]
-      [no/off: disable the optimizations;]
+      [no/off: disable the optimizations; check: use internal checking code]
-      [check: use internal checking code (deprecated and poorly supported);]
+      [(deprecated and poorly supported); api: disable by default, enable by]
-      [api: disable by default, enable by a call to png_set_option;]
+      [a call to png_set_option; yes/on: turn on unconditionally.]
      [yes/on: turn on unconditionally.]
      [If not specified: determined by the compiler.]),
   [case "$enableval" in
      no|off)
@ -450,7 +412,7 @@ AC_ARG_ENABLE([mips-msa],
         AC_DEFINE([PNG_MIPS_MSA_OPT], [0],
                   [Disable MIPS MSA optimizations])
         # Prevent inclusion of the assembler files below:
-         enable_mips_msa=no ;;
+         enable_mips_msa=no;;
      check)
         AC_DEFINE([PNG_MIPS_MSA_CHECK_SUPPORTED], [],
                   [Check for MIPS MSA support at run-time]);;
@ -460,75 +422,31 @@ AC_ARG_ENABLE([mips-msa],
      yes|on)
         AC_DEFINE([PNG_MIPS_MSA_OPT], [2],
                   [Enable MIPS MSA optimizations])
-         AC_MSG_WARN([--enable-mips-msa: please specify 'check' or 'api';]
+         AC_MSG_WARN([--enable-mips-msa: please specify 'check' or 'api', if]
-            [if you want the optimizations unconditionally,]
+            [you want the optimizations unconditionally pass '-mmsa -mfp64']
-            [pass '-mmsa -mfp64' to the compiler.]);;
+            [to the compiler.]);;
      *)
-         AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}:]
+         AC_MSG_ERROR([--enable-mips-msa=${enable_mips_msa}: invalid value])
                      [invalid argument])
   esac])
-# Add MIPS-specific files to all builds where $host_cpu is mips ('mips*') or
+# Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
-# where MIPS optimizations were explicitly requested. (This allows a fallback
+# where MIPS optimizations were explicitly requested (this allows a fallback if a
-# if a future host CPU does not match 'mips*'.)
+# future host CPU does not match 'mips*')
 AM_CONDITIONAL([PNG_MIPS_MSA],
   [test "$enable_mips_msa" != 'no' &&
    case "$host_cpu" in
-      mipsel*|mips64el*) : ;;
+      mipsel*|mips64el*) :;;
    esac])
-# MIPS MMI
+# INTEL
-# ========
+# =====
-
+#
-AC_ARG_ENABLE([mips-mmi],
+# INTEL SSE (SIMD) support.
   AS_HELP_STRING([[[--enable-mips-mmi]]],
      [Enable MIPS MMI optimizations: =no/off, check, api, yes/on.]
      [no/off: disable the optimizations;]
      [check: use internal checking code (deprecated and poorly supported);]
      [api: disable by default, enable by a call to png_set_option;]
      [yes/on: turn on unconditionally.]
      [If not specified: determined by the compiler.]),
   [case "$enableval" in
      no|off)
         # disable the default enabling on __mips_mmi systems:
         AC_DEFINE([PNG_MIPS_MMI_OPT], [0],
                   [Disable MIPS MMI optimizations])
         # Prevent inclusion of the assembler files below:
         enable_mips_mmi=no;;
      check)
         AC_DEFINE([PNG_MIPS_MMI_CHECK_SUPPORTED], [],
                   [Check for MIPS MMI support at run-time]);;
      api)
         AC_DEFINE([PNG_MIPS_MMI_API_SUPPORTED], [],
                   [Turn on MIPS MMI optimizations at run-time]);;
      yes|on)
         AC_DEFINE([PNG_MIPS_MMI_OPT], [1],
                   [Enable MIPS MMI optimizations])
         AC_MSG_WARN([--enable-mips-mmi: please specify 'check' or 'api';]
            [if you want the optimizations unconditionally]
            [pass '-mloongson-mmi -march=loongson3a' to the compiler.]);;
      *)
         AC_MSG_ERROR([--enable-mips-mmi=${enable_mips_mmi}:]
                      [invalid argument])
   esac])
 # Add MIPS specific files to all builds where the host_cpu is mips ('mips*') or
 # where MIPS optimizations were explicitly requested. (This allows a fallback
 # if a future host CPU does not match 'mips*'.)
 AM_CONDITIONAL([PNG_MIPS_MMI],
   [test "$enable_mips_mmi" != 'no' &&
    case "$host_cpu" in
      mipsel*|mips64el*) : ;;
    esac])
 # INTEL SSE
 # =========
 AC_ARG_ENABLE([intel-sse],
   AS_HELP_STRING([[[--enable-intel-sse]]],
-      [Enable Intel SSE optimizations: =no/off, yes/on.]
+      [Enable Intel SSE optimizations: =no/off, yes/on:]
      [no/off: disable the optimizations;]
      [yes/on: enable the optimizations.]
      [If not specified: determined by the compiler.]),
@ -538,34 +456,34 @@ AC_ARG_ENABLE([intel-sse],
         AC_DEFINE([PNG_INTEL_SSE_OPT], [0],
                   [Disable Intel SSE optimizations])
         # Prevent inclusion of the assembler files below:
-         enable_intel_sse=no ;;
+         enable_intel_sse=no;;
      yes|on)
         AC_DEFINE([PNG_INTEL_SSE_OPT], [1],
                   [Enable Intel SSE optimizations]);;
      *)
-         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}:]
+         AC_MSG_ERROR([--enable-intel-sse=${enable_intel_sse}: invalid value])
                      [invalid argument])
   esac])
-# Add Intel-specific files to all builds where $host_cpu is Intel ('x86*') or
+# Add Intel specific files to all builds where the host_cpu is Intel ('x86*')
-# where Intel optimizations were explicitly requested. (This allows a fallback
+# or where Intel optimizations were explicitly requested (this allows a
-# if a future host CPU does not match 'x86*'.)
+# fallback if a future host CPU does not match 'x86*')
 AM_CONDITIONAL([PNG_INTEL_SSE],
   [test "$enable_intel_sse" != 'no' &&
    case "$host_cpu" in
-      i?86|x86_64) : ;;
+      i?86|x86_64) :;;
-      *)    test "$enable_intel_sse" != '' ;;
+      *)    test "$enable_intel_sse" != '';;
    esac])
-# POWERPC VSX
+# PowerPC
-# ===========
+# ===
 #
 # PowerPC VSX (SIMD) support.
 AC_ARG_ENABLE([powerpc-vsx],
 AS_HELP_STRING([[[--enable-powerpc-vsx]]],
-      [Enable POWERPC VSX optimizations: =no/off, check, api, yes/on.]
+      [Enable POWERPC VSX optimizations: =no/off, check, api, yes/on:]
-      [no/off: disable the optimizations;]
+      [no/off: disable the optimizations; check: use internal checking code]
-      [check: use internal checking code;]
+      [api: disable by default, enable by a call to png_set_option]
      [api: disable by default, enable by a call to png_set_option;]
      [yes/on: turn on unconditionally.]
      [If not specified: determined by the compiler.]),
   [case "$enableval" in
@ -573,171 +491,36 @@ AS_HELP_STRING([[[--enable-powerpc-vsx]]],
         # disable the default enabling on __ppc64__ systems:
         AC_DEFINE([PNG_POWERPC_VSX_OPT], [0],
                   [Disable POWERPC VSX optimizations])
-         # Prevent inclusion of the platform-specific files below:
+         # Prevent inclusion of the platform specific files below:
-         enable_powerpc_vsx=no ;;
+         enable_powerpc_vsx=no;;
      check)
         AC_DEFINE([PNG_POWERPC_VSX_CHECK_SUPPORTED], [],
                   [Check for POWERPC VSX support at run-time])
-         AC_MSG_WARN([--enable-powerpc-vsx: please see contrib/powerpc/README]
+         AC_MSG_WARN([--enable-powerpc-vsx Please check contrib/powerpc/README file]
-                     [for the list of supported systems.]);;
+            [for the list of supported OSes.]);;
      api)
         AC_DEFINE([PNG_POWERPC_VSX_API_SUPPORTED], [],
                   [Turn on POWERPC VSX optimizations at run-time]);;
      yes|on)
         AC_DEFINE([PNG_POWERPC_VSX_OPT], [2],
                   [Enable POWERPC VSX optimizations])
-         AC_MSG_WARN([--enable-powerpc-vsx: please specify 'check' or 'api';]
+         AC_MSG_WARN([--enable-powerpc-vsx: please specify 'check' or 'api', if]
-            [if you want the optimizations unconditionally,]
+            [you want the optimizations unconditionally pass '-maltivec -mvsx']
-            [pass '-maltivec -mvsx' or '-mcpu=power8' to the compiler.]);;
+            [or '-mcpu=power8'to the compiler.]);;
      *)
-         AC_MSG_ERROR([--enable-powerpc-vsx=${enable_powerpc_vsx}:]
+         AC_MSG_ERROR([--enable-powerpc-vsx=${enable_powerpc_vsx}: invalid value])
                      [invalid argument])
   esac])
-# Add PowerPC-specific files to all builds where $host_cpu is powerpc
+# Add PowerPC specific files to all builds where the host_cpu is powerpc('powerpc*') or
-# ('powerpc*') or where PowerPC optimizations were explicitly requested.
+# where POWERPC optimizations were explicitly requested (this allows a fallback if a
-# (This allows a fallback if a future host CPU does not match 'powerpc*'.)
+# future host CPU does not match 'powerpc*')
 AM_CONDITIONAL([PNG_POWERPC_VSX],
   [test "$enable_powerpc_vsx" != 'no' &&
    case "$host_cpu" in
-      powerpc*|ppc64*) : ;;
+      powerpc*|ppc64*) :;;
    esac])
 # LOONGARCH LSX
 # =============
 AC_ARG_ENABLE([loongarch-lsx],
   AS_HELP_STRING([[[--enable-loongarch-lsx]]],
      [Enable LOONGARCH LSX optimizations: =no/off, yes/on:]
      [no/off: disable the optimizations;]
      [yes/on: turn on unconditionally.]
      [If not specified: determined by the compiler.]),
   [case "$enableval" in
      no|off)
         # disable the default enabling on __loongarch_simd systems:
         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [0],
                   [Disable LOONGARCH LSX optimizations])
         # Prevent inclusion of the assembler files below:
         enable_loongarch_lsx=no;;
      yes|on)
         AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1],
                   [Enable LOONGARCH LSX optimizations])
         ;;
      *)
         AC_MSG_ERROR([--enable-loongarch-lsx=${enable_loongarch_lsx}:]
                      [invalid argument])
   esac])
 if test "$enable_loongarch_lsx" != "no" &&
   case "$host_cpu" in
      loongarch*) : ;;
      *)    test "$enable_loongarch_lsx" != '' ;;
   esac
 then
   compiler_support_loongarch_lsx=no
   AC_MSG_CHECKING(whether to use LoongArch LSX intrinsics)
   save_CFLAGS="$CFLAGS"
   LSX_CFLAGS="${LSX_CFLAGS:-"-mlsx"}"
   CFLAGS="$CFLAGS $LSX_CFLAGS"
   AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #include <lsxintrin.h>
 int main(){
   __m128i a, b, c;
   a = __lsx_vadd_w(b, c);
   return 0;
 }]])],compiler_support_loongarch_lsx=yes)
   CFLAGS="$save_CFLAGS"
   AC_MSG_RESULT($compiler_support_loongarch_lsx)
   if test "$compiler_support_loongarch_lsx" = "yes"; then
      AC_DEFINE([PNG_LOONGARCH_LSX_OPT], [1],
                [Enable LOONGARCH LSX optimizations])
   else
      AC_MSG_WARN([Compiler does not support loongarch LSX.])
   fi
 fi
 # Add LoongArch specific files to all builds where the host_cpu is loongarch
 # ('loongarch*') or where LoongArch optimizations were explicitly requested.
 # (This allows a fallback if a future host CPU does not match 'loongarch*'.)
 AM_CONDITIONAL([PNG_LOONGARCH_LSX],
   [test "$enable_loongarch_lsx" != "no" &&
    test "$compiler_support_loongarch_lsx" = "yes" &&
    case "$host_cpu" in
      loongarch*) : ;;
      *)    test "$enable_loongarch_lsx" != '' ;;
    esac])
 # RISC-V
 # ======
 #
 # RISC-V Vector support.
 AC_ARG_ENABLE([riscv-rvv],
 AS_HELP_STRING([[[--enable-riscv-rvv]]],
      [Enable RISC-V Vector optimizations: =no/off, check, api, yes/on:]
      [no/off: disable the optimizations; check: use internal checking code]
      [api: disable by default, enable by a call to png_set_option]
      [yes/on: turn on. If not specified: determined by the compiler.]),
   [case "$enableval" in
      no|off)
         # disable the default enabling on __riscv systems:
         AC_DEFINE([PNG_RISCV_RVV_OPT], [0],
                   [Disable RISC-V Vector optimizations])
         # Prevent inclusion of the platform-specific files below:
         enable_riscv_rvv=no ;;
      yes|on)
         AC_DEFINE([PNG_RISCV_RVV_OPT], [2],
                   [Enable RISC-V Vector optimizations])
         AC_MSG_WARN([--enable-riscv-rvv:]
            [if you want the optimizations pass e.g. '-march=rv64gv1p0' to the compiler.]);;
      *)
         AC_MSG_ERROR([--enable-riscv-rvv=${enable_riscv_rvv}: invalid value])
   esac])
 if test "$enable_riscv_rvv" != "no" &&
   case "$host_cpu" in
      riscv64) : ;;
      *)    test "$enable_riscv_rvv" != '' ;;
   esac
 then
   compiler_support_riscv_rvv=no
   AC_MSG_CHECKING(whether to use RISC-V RVV intrinsics)
   AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #include <riscv_vector.h>
 #include <asm/hwcap.h>
 #ifndef COMPAT_HWCAP_ISA_V /* added in linux-6.5 */
 #error "COMPAT_HWCAP_ISA_V is not available"
 #endif
 int main() {
   const float src[] = { 0.0f, 0.0f, 0.0f, 0.0f };
   uint64_t ptr[2] = {0x0908060504020100, 0xFFFFFFFF0E0D0C0A};
   vuint8m1_t a = __riscv_vreinterpret_v_u64m1_u8m1(__riscv_vle64_v_u64m1(ptr, 2));
   vfloat32m1_t val = __riscv_vle32_v_f32m1((const float*)(src), 4);
   return (int)__riscv_vfmv_f_s_f32m1_f32(val);
 }]])],compiler_support_riscv_rvv=yes)
   AC_MSG_RESULT($compiler_support_riscv_rvv)
   if test "$compiler_support_riscv_rvv" = "yes"; then
      AC_DEFINE([PNG_RISCV_RVV_OPT], [1],
                [Enable RISCV RVV optimizations])
   else
      AC_MSG_WARN([Compiler does not support riscv rvv.])
   fi
 fi
 # Add RISC-V-specific files to all builds where $host_cpu is riscv ('riscv64')
 # or where RISC-V optimizations were explicitly requested (this allows a fallback
 # if a future host CPU does not match 'riscv64')
 AM_CONDITIONAL([PNG_RISCV_RVV],
   [test "$enable_riscv_rvv" != "no" &&
    test "$compiler_support_riscv_rvv" = "yes" &&
    case "$host_cpu" in
      riscv64) : ;;
      *)    test "$compiler_support_riscv_rvv" != '' ;;
    esac])
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
--- a/contrib/.editorconfig
+++ b/contrib/.editorconfig
@ -1,9 +0,0 @@
 # https://editorconfig.org
 root = false
 [*.[ch]]
 indent_size = unset
 indent_style = unset
 max_doc_length = unset
 max_line_length = unset
--- a/contrib/README.txt
+++ b/contrib/README.txt
@ -1,5 +1,3 @@
 External contributions to libpng
 --------------------------------
 This "contrib" directory contains contributions which are not necessarily under
 the libpng license, although all are open source.  They are not part of
--- a/contrib/arm-neon/android-ndk.c
+++ b/contrib/arm-neon/android-ndk.c
@ -2,6 +2,7 @@
 *
 * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by John Bowler, 2014.
 * Last changed in libpng 1.6.10 [March 6, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@ -23,7 +24,6 @@
 * has been compiled only, not linked: no version of the library has been found,
 * only the header files exist in the NDK.
 */
 #include <cpu-features.h>
 static int
--- a/contrib/arm-neon/linux-auxv.c
+++ b/contrib/arm-neon/linux-auxv.c
@ -2,6 +2,7 @@
 *
 * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
 * Last changed in libpng 1.6.10 [March 6, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@ -21,7 +22,6 @@
 * This generic __linux__ implementation requires reading /proc/self/auxv and
 * looking at each element for one that records NEON capabilities.
 */
 #include <unistd.h> /* for POSIX 1003.1 */
 #include <errno.h>  /* for EINTR */
--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@ -1,5 +1,6 @@
 /* contrib/arm-neon/linux.c
 *
 * Last changed in libpng 1.6.31 [July 27, 2017]
 * Copyright (c) 2014, 2017 Glenn Randers-Pehrson
 * Written by John Bowler, 2014, 2017.
 *
@ -18,7 +19,6 @@
 * This code is strict ANSI-C and is probably moderately portable; it does
 * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
 */
 #include <stdio.h>
 static int
--- a/contrib/conftest/basic.dfa
+++ b/contrib/conftest/basic.dfa
@ -1,133 +0,0 @@
 # basic.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2024
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Build libpng with basic read and write support.  This enables the lowest
 # level libpng read and write APIs - the "row-by-row" ones.
 #
 # Support is enabled only for those transformations that are observed to be
 # required by widely used apps or are in the v3 specification.
 #
 everything = off
 # The sequential read code is enabled here; the progressive code can be used
 # instead but there is no point enabling both.
 option READ on
 option SEQUENTIAL_READ on
 option EASY_ACCESS on
 option SET_USER_LIMITS on
 option INFO_IMAGE on
 option READ_16BIT on
 # Errors: these can be disabled but then there won't be any error messages
 # just failures and the error messages are really needed for apps:
 option WARNINGS on
 option ERROR_TEXT on
 option BENIGN_READ_ERRORS on
 # Required for many display programs such as web browsers:
 option PROGRESSIVE_READ on
 # Switch on the write code - this makes a minimalist encoder but with
 # interlace support turned on; otherwise png_read_png..png_write_png will
 # fail on an interlaced image.
 option WRITE on
 option WRITE_INTERLACING on
 option WRITE_16BIT on
 # Usages of the 'fixed' APIs are relatively rare but they do occur
 # one or the other for both the API and the internal math.
 #Fixed point:
 option FIXED_POINT on
 #Floating point:
 option FLOATING_POINT on
 option FLOATING_ARITHMETIC on
 # Basic error handling, IO and user memory support.  The latter allows the
 # application program to provide its own implementations of 'malloc' and 'free'.
 option SETJMP on
 option STDIO on
 option USER_MEM on
 # Gamma handling: this needs to be on for the gamma handling
 option READ_GAMMA on
 # The supported chunks
 chunk bKGD on
 chunk cHRM on
 chunk eXIf on
 chunk gAMA on
 chunk iCCP on
 chunk iTXt on
 chunk pHYs on
 chunk sBIT on
 chunk sRGB on
 chunk tEXt on
 chunk tIME on
 chunk tRNS on
 chunk zTXt on
 # These don't seem to be used anywhere:
 # chunk pCAL
 # chunk sCAL
 # chunk sPLT
 # The rest of this is app dependent: none of these options are required for
 # read/write of the full range of PNG files and the normal chunk handling on
 # read.
 option WRITE_CUSTOMIZE_ZTXT_COMPRESSION on
 option WRITE_CUSTOMIZE_COMPRESSION on
 option READ_EXPAND on
 option READ_FILLER on
 option READ_GRAY_TO_RGB on
 option READ_INVERT on
 option READ_PACK on
 option READ_RGB_TO_GRAY on
 option READ_SCALE_16_TO_8 on
 option READ_SHIFT on
 option READ_STRIP_16_TO_8 on
 option READ_STRIP_ALPHA on
 option READ_SWAP on
 option CONVERT_tIME on
 # optipng
 option IO_STATE on
 option STORE_UNKNOWN_CHUNKS on
 option HANDLE_AS_UNKNOWN on
 # pngcrush
 option READ_USER_TRANSFORM on
 option WRITE_FLUSH on
 # pnmtopng
 chunk hIST on
 # cairo
 option WRITE_PACKSWAP on
 option WRITE_USER_TRANSFORM on
 # graphicsmagick
 option READ_USER_CHUNKS on
 # Qt5.15 qtgui (gentoo package split) Qt6.6 qtbase
 option READ_BGR on
 option WRITE_BGR on
 option READ_SWAP_ALPHA on
 option WRITE_SWAP_ALPHA on
 chunk oFFs on
 # ghostscript-gpl
 option WRITE_INVERT_ALPHA on
 option WRITE_INVERT on
--- a/contrib/conftest/fixed.dfa
+++ b/contrib/conftest/fixed.dfa
@ -1,15 +0,0 @@
 # fixed.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Test the standard libpng configuration without floating point (the internal
 # fixed point implementations are used instead).
 #
 option FLOATING_ARITHMETIC off
 option FLOATING_POINT off
--- a/contrib/conftest/float-fixed.dfa
+++ b/contrib/conftest/float-fixed.dfa
@ -1,14 +0,0 @@
 # fixed-float.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Test the standard libpng configuration with the fixed point internal
 # implementation in place of the default floating point
 #
 option FLOATING_ARITHMETIC off
--- a/contrib/conftest/nocompile-limits.dfa
+++ b/contrib/conftest/nocompile-limits.dfa
@ -1,21 +0,0 @@
 # nolimits.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 #
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Build libpng without any limits and without run-time settable limits.  Turning
 # USER_LIMITS off reduces libpng code size by allowing compile-time elimination
 # of some checking code.
 #
 option USER_LIMITS off
@# define PNG_USER_WIDTH_MAX PNG_UINT_31_MAX
@# define PNG_USER_HEIGHT_MAX PNG_UINT_31_MAX
@# define PNG_USER_CHUNK_CACHE_MAX 0
@# define PNG_USER_CHUNK_MALLOC_MAX 0
--- a/contrib/conftest/nolimits.dfa
+++ b/contrib/conftest/nolimits.dfa
@ -1,19 +0,0 @@
 # nolimits.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 #
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Build libpng without any limits.  With these settigs run-time limits are still
 # possible.
 #
@# define PNG_USER_WIDTH_MAX PNG_UINT_31_MAX
@# define PNG_USER_HEIGHT_MAX PNG_UINT_31_MAX
@# define PNG_USER_CHUNK_CACHE_MAX 0
@# define PNG_USER_CHUNK_MALLOC_MAX 0
--- a/contrib/conftest/read-full.dfa
+++ b/contrib/conftest/read-full.dfa
@ -1,13 +0,0 @@
 # read-full.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Build libpng with no write support and full read support.
 #
 option WRITE off
--- a/contrib/conftest/write-full.dfa
+++ b/contrib/conftest/write-full.dfa
@ -1,13 +0,0 @@
 # write-full.dfa
 #  Build time configuration of libpng
 #
 # Author: John Bowler
 # Copyright: (c) John Bowler, 2025
 # Usage rights:
 #  To the extent possible under law, the author has waived all copyright and
 #  related or neighboring rights to this work.  This work is published from:
 #  United States.
 #
 # Build libpng with no read support and full write support.
 #
 option READ off
--- a/contrib/examples/.clang-format
+++ b/contrib/examples/.clang-format
@ -1,143 +0,0 @@
 ---
 Language: Cpp
 AccessModifierOffset: -3
 AlignAfterOpenBracket: Align
 AlignArrayOfStructures: None
 AlignConsecutiveAssignments:
  Enabled: false
 AlignConsecutiveBitFields:
  Enabled: false
 AlignConsecutiveDeclarations:
  Enabled: false
 AlignConsecutiveMacros:
  Enabled: false
 AlignConsecutiveShortCaseStatements:
  Enabled: false
 AlignEscapedNewlines: DontAlign
 AlignOperands: false
 AlignTrailingComments:
  Kind: Never
  OverEmptyLines: 0
 AllowAllArgumentsOnNextLine: true
 AllowAllParametersOfDeclarationOnNextLine: true
 AllowBreakBeforeNoexceptSpecifier: Never
 AllowShortBlocksOnASingleLine: Never
 AllowShortCaseExpressionOnASingleLine: true
 AllowShortCaseLabelsOnASingleLine: true
 AllowShortCompoundRequirementOnASingleLine: true
 AllowShortEnumsOnASingleLine: false
 AllowShortFunctionsOnASingleLine: None
 AllowShortIfStatementsOnASingleLine: Never
 AllowShortLambdasOnASingleLine: All
 AllowShortLoopsOnASingleLine: false
 AllowShortNamespacesOnASingleLine: false
 AlwaysBreakBeforeMultilineStrings: false
 BinPackArguments: true
 BinPackParameters: BinPack
 BitFieldColonSpacing: Both
 BraceWrapping:
  AfterCaseLabel: true
  AfterClass: true
  AfterControlStatement: Always
  AfterEnum: true
  AfterExternBlock: false
  AfterFunction: true
  AfterNamespace: false
  AfterObjCDeclaration: true
  AfterStruct: true
  AfterUnion: true
  BeforeCatch: true
  BeforeElse: true
  BeforeLambdaBody: false
  BeforeWhile: false
  IndentBraces: false
  SplitEmptyFunction: true
  SplitEmptyRecord: true
  SplitEmptyNamespace: true
 BreakAdjacentStringLiterals: true
 BreakAfterAttributes: Leave
 BreakAfterJavaFieldAnnotations: false
 BreakAfterReturnType: TopLevel
 BreakArrays: true
 BreakBeforeBinaryOperators: None
 BreakBeforeConceptDeclarations: Always
 BreakBeforeBraces: Custom
 BreakBeforeTernaryOperators: false
 BreakStringLiterals: false
 BreakTemplateDeclarations: MultiLine
 ColumnLimit: 79
 ContinuationIndentWidth: 3
 DerivePointerAlignment: true
 EmptyLineAfterAccessModifier: Never
 EmptyLineBeforeAccessModifier: LogicalBlock
 FixNamespaceComments: true
 IncludeBlocks: Preserve
 IndentAccessModifiers: false
 IndentCaseBlocks: true
 IndentCaseLabels: true
 IndentExportBlock: true
 IndentExternBlock: AfterExternBlock
 IndentGotoLabels: false
 IndentPPDirectives: None
 IndentRequiresClause: true
 IndentWidth: 3
 IndentWrappedFunctionNames: false
 KeepEmptyLines:
  AtEndOfFile: false
  AtStartOfBlock: false
  AtStartOfFile: false
 KeepFormFeed: false
 MaxEmptyLinesToKeep: 2
 NamespaceIndentation: None
 PackConstructorInitializers: Never
 PointerAlignment: Left
 QualifierAlignment: Custom
 QualifierOrder: [static, inline, constexpr, const, volatile, restrict, type]
 ReferenceAlignment: Pointer
 ReflowComments: Never
 RequiresClausePosition: OwnLine
 RequiresExpressionIndentation: OuterScope
 SortIncludes: false
 SortUsingDeclarations: LexicographicNumeric
 SpaceAfterCStyleCast: false
 SpaceAfterLogicalNot: false
 SpaceAfterTemplateKeyword: true
 SpaceAroundPointerQualifiers: Default
 SpaceBeforeAssignmentOperators: true
 SpaceBeforeCaseColon: false
 SpaceBeforeCpp11BracedList: false
 SpaceBeforeCtorInitializerColon: true
 SpaceBeforeInheritanceColon: true
 SpaceBeforeJsonColon: false
 SpaceBeforeParens: ControlStatements
 SpaceBeforeParensOptions:
  AfterControlStatements: true
  AfterFunctionDefinitionName: false
  AfterFunctionDeclarationName: false
  AfterOverloadedOperator: false
  AfterPlacementOperator: true
  AfterRequiresInClause: false
  AfterRequiresInExpression: false
  BeforeNonEmptyParentheses: false
 SpaceBeforeRangeBasedForLoopColon: true
 SpaceBeforeSquareBrackets: false
 SpaceInEmptyBlock: false
 SpacesBeforeTrailingComments: 1
 SpacesInAngles: Never
 SpacesInContainerLiterals: true
 SpacesInLineCommentPrefix:
  Minimum: 1
  Maximum: -1
 SpacesInParens: Never
 SpacesInParensOptions:
  ExceptDoubleParentheses: false
  InCStyleCasts: false
  InConditionalStatements: false
  InEmptyParentheses: false
  Other: false
 SpacesInSquareBrackets: false
 Standard: Latest
 TabWidth: 8
 UseTab: Never
 WrapNamespaceBodyWithEmptyLines: Leave
 ...
--- a/contrib/examples/README.txt
+++ b/contrib/examples/README.txt
@ -1,3 +1,4 @@
 This directory (contrib/examples) contains examples of libpng usage.
 NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.
--- a/contrib/examples/iccfrompng.c
+++ b/contrib/examples/iccfrompng.c
@ -26,9 +26,8 @@
 #include <png.h>
-#if !defined(PNG_iCCP_SUPPORTED) || !defined(PNG_READ_SUPPORTED)
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_STDIO_SUPPORTED) && \
-#error This program requires libpng supporting the iCCP chunk and the read API
+    defined (PNG_iCCP_SUPPORTED)
 #endif
 static int verbose = 1;
@ -37,8 +36,7 @@ static png_byte no_profile[] = "no profile";
 static png_bytep
 extract(FILE *fp, png_uint_32 *proflen)
 {
-   png_structp png_ptr =
+   png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,0,0,0);
      png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
   png_infop info_ptr = NULL;
   png_bytep result = NULL;
@ -71,7 +69,7 @@ extract(FILE *fp, png_uint_32 *proflen)
      png_bytep profile;
      if (png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, &profile,
-                       proflen) & PNG_INFO_iCCP)
+         proflen) & PNG_INFO_iCCP)
      {
         result = malloc(*proflen);
         if (result != NULL)
@ -82,7 +80,7 @@ extract(FILE *fp, png_uint_32 *proflen)
      }
      else
-         result = no_profile;
+	result = no_profile;
   }
   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
@ -109,7 +107,7 @@ extract_one_file(const char *filename)
            const char *ep = strrchr(filename, '.');
            if (ep != NULL)
-               len = ep - filename;
+               len = ep-filename;
            else
               len = strlen(filename);
@ -121,14 +119,14 @@ extract_one_file(const char *filename)
            FILE *of;
            memcpy(output, filename, len);
-            strcpy(output + len, ".icc");
+            strcpy(output+len, ".icc");
            of = fopen(output, "wb");
            if (of != NULL)
            {
               if (fwrite(profile, proflen, 1, of) == 1 &&
-                   fflush(of) == 0 &&
+                  fflush(of) == 0 &&
-                   fclose(of) == 0)
+                  fclose(of) == 0)
               {
                  if (verbose)
                     printf("%s -> %s\n", filename, output);
@ -157,15 +155,12 @@ extract_one_file(const char *filename)
      }
      else if (verbose && profile == no_profile)
-         printf("%s has no profile\n", filename);
+	printf("%s has no profile\n", filename);
   }
   else
      fprintf(stderr, "%s: could not open file\n", filename);
   if (fp != NULL)
      fclose(fp);
   return result;
 }
@ -175,7 +170,7 @@ main(int argc, char **argv)
   int i;
   int extracted = 0;
-   for (i = 1; i < argc; ++i)
+   for (i=1; i<argc; ++i)
   {
      if (strcmp(argv[i], "-q") == 0)
         verbose = 0;
@ -187,3 +182,4 @@ main(int argc, char **argv)
   /* Exit code is true if any extract succeeds */
   return extracted == 0;
 }
 #endif /* READ && STDIO && iCCP */
--- a/contrib/examples/pngpixel.c
+++ b/contrib/examples/pngpixel.c
@ -15,8 +15,8 @@
 * images.  Normally you would call png_set_interlace_handling() to have libpng
 * deal with the interlace for you, but that obliges you to buffer half of the
 * image to assemble the interlaced rows.  In this code
- * png_set_interlace_handling() is not called and, instead, the code handles
+ * png_set_interlace_handling() is not called and, instead, the code handles the
- * the interlace passes directly looking for the required pixel.
+ * interlace passes directly looking for the required pixel.
 */
 #include <stdlib.h>
 #include <stdio.h>
@ -27,37 +27,34 @@
 */
 #include "../../png.h"
-#if !defined(PNG_READ_SUPPORTED) || !defined(PNG_SEQUENTIAL_READ_SUPPORTED)
+#if defined(PNG_READ_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)
 #error This program requires libpng supporting the read and sequential read API
 #endif
 /* Return component 'c' of pixel 'x' from the given row. */
 static unsigned int
 component(png_const_bytep row, png_uint_32 x, unsigned int c,
-          unsigned int bit_depth, unsigned int channels)
+   unsigned int bit_depth, unsigned int channels)
 {
-   /* PNG images can be up to 2^31 pixels wide, which means they can be up to
+   /* PNG images can be up to 2^31 pixels wide, but this means they can be up to
-    * 2^37 bits wide (for a 64-bit pixel - the largest possible) and hence
+    * 2^37 bits wide (for a 64-bit pixel - the largest possible) and hence 2^34
-    * 2^34 bytes wide.  Since the row fitted into memory, the following must
+    * bytes wide.  Since the row fitted into memory, however, the following must
    * work:
    */
   png_uint_32 bit_offset_hi = bit_depth * ((x >> 6) * channels);
   png_uint_32 bit_offset_lo = bit_depth * ((x & 0x3f) * channels + c);
-   row = (png_const_bytep)(((const png_byte(*)[8])row) + bit_offset_hi);
+   row = (png_const_bytep)(((const png_byte (*)[8])row) + bit_offset_hi);
   row += bit_offset_lo >> 3;
   bit_offset_lo &= 0x07;
   /* PNG pixels are packed into bytes to put the first pixel in the highest
-    * bits of the byte, and into two bytes for 16-bit values with the high
+    * bits of the byte and into two bytes for 16-bit values with the high 8 bits
-    * 8 bits first, so:
+    * first, so:
    */
   switch (bit_depth)
   {
-      case 1: return (row[0] >> (7 - bit_offset_lo)) & 0x01;
+      case 1: return (row[0] >> (7-bit_offset_lo)) & 0x01;
-      case 2: return (row[0] >> (6 - bit_offset_lo)) & 0x03;
+      case 2: return (row[0] >> (6-bit_offset_lo)) & 0x03;
-      case 4: return (row[0] >> (4 - bit_offset_lo)) & 0x0f;
+      case 4: return (row[0] >> (4-bit_offset_lo)) & 0x0f;
      case 8: return row[0];
      case 16: return (row[0] << 8) + row[1];
      default:
@ -74,7 +71,7 @@ component(png_const_bytep row, png_uint_32 x, unsigned int c,
 */
 static void
 print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
-            png_uint_32 x)
+   png_uint_32 x)
 {
   unsigned int bit_depth = png_get_bit_depth(png_ptr, info_ptr);
@ -95,24 +92,22 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
            int num_palette = 0;
            if ((png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) &
-                 PNG_INFO_PLTE) &&
+               PNG_INFO_PLTE) && num_palette > 0 && palette != NULL)
                (num_palette > 0) &&
                (palette != NULL))
            {
               png_bytep trans_alpha = NULL;
               int num_trans = 0;
               if ((png_get_tRNS(png_ptr, info_ptr, &trans_alpha, &num_trans,
-                                 NULL) & PNG_INFO_tRNS) &&
+                  NULL) & PNG_INFO_tRNS) && num_trans > 0 &&
-                   (num_trans > 0) &&
+                  trans_alpha != NULL)
                   (trans_alpha != NULL))
                  printf("INDEXED %u = %d %d %d %d\n", index,
-                         palette[index].red, palette[index].green,
+                     palette[index].red, palette[index].green,
-                         palette[index].blue,
+                     palette[index].blue,
-                         index < num_trans ? trans_alpha[index] : 255);
+                     index < num_trans ? trans_alpha[index] : 255);
               else /* no transparency */
-                  printf("INDEXED %u = %d %d %d\n", index, palette[index].red,
+                  printf("INDEXED %u = %d %d %d\n", index,
-                         palette[index].green, palette[index].blue);
+                     palette[index].red, palette[index].green,
                     palette[index].blue);
            }
            else
@ -122,20 +117,20 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
      case PNG_COLOR_TYPE_RGB:
         printf("RGB %u %u %u\n", component(row, x, 0, bit_depth, 3),
-                component(row, x, 1, bit_depth, 3),
+            component(row, x, 1, bit_depth, 3),
-                component(row, x, 2, bit_depth, 3));
+            component(row, x, 2, bit_depth, 3));
         return;
      case PNG_COLOR_TYPE_GRAY_ALPHA:
         printf("GRAY+ALPHA %u %u\n", component(row, x, 0, bit_depth, 2),
-                component(row, x, 1, bit_depth, 2));
+            component(row, x, 1, bit_depth, 2));
         return;
      case PNG_COLOR_TYPE_RGB_ALPHA:
         printf("RGBA %u %u %u %u\n", component(row, x, 0, bit_depth, 4),
-                component(row, x, 1, bit_depth, 4),
+            component(row, x, 1, bit_depth, 4),
-                component(row, x, 2, bit_depth, 4),
+            component(row, x, 2, bit_depth, 4),
-                component(row, x, 3, bit_depth, 4));
+            component(row, x, 3, bit_depth, 4));
         return;
      default:
@ -143,8 +138,7 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
   }
 }
-int
+int main(int argc, const char **argv)
 main(int argc, const char **argv)
 {
   /* This program uses the default, <setjmp.h> based, libpng error handling
    * mechanism, therefore any local variable that exists before the call to
@ -152,7 +146,7 @@ main(int argc, const char **argv)
    * be declared with 'volatile' to ensure that their values don't get
    * destroyed by longjmp:
    */
-   volatile int result = 1 /*fail*/;
+   volatile int result = 1/*fail*/;
   if (argc == 4)
   {
@ -169,8 +163,8 @@ main(int argc, const char **argv)
          * writes error messages to stderr.  Creating the png_struct is a
          * little tricky; just copy the following code.
          */
-         png_structp png_ptr =
+         png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
-            png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+            NULL, NULL, NULL);
         if (png_ptr != NULL)
         {
@ -190,11 +184,11 @@ main(int argc, const char **argv)
                     compression_method, filter_method;
                  png_bytep row_tmp;
-                  /* Now associate the recently opened FILE object with the
+                  /* Now associate the recently opened (FILE*) with the default
-                   * default libpng initialization functions.  Sometimes libpng
+                   * libpng initialization functions.  Sometimes libpng is
-                   * is compiled without stdio support (it can be difficult to
+                   * compiled without stdio support (it can be difficult to do
-                   * do in some environments); in that case you will have to
+                   * in some environments); in that case you will have to write
-                   * write your own read callback to read data from the stream.
+                   * your own read callback to read data from the (FILE*).
                   */
                  png_init_io(png_ptr, f);
@ -208,21 +202,21 @@ main(int argc, const char **argv)
                   * space.  In this case png_malloc is used - it will not
                   * return if memory isn't available.
                   */
-                  row =
+                  row = png_malloc(png_ptr, png_get_rowbytes(png_ptr,
-                     png_malloc(png_ptr, png_get_rowbytes(png_ptr, info_ptr));
+                     info_ptr));
-                  /* Avoid the overhead of using a volatile auto copy row_tmp
+                  /* To avoid the overhead of using a volatile auto copy row_tmp
                   * to a local here - just use row for the png_free below.
                   */
                  row_tmp = row;
-                  /* All the information we need is in the header returned by
+                  /* All the information we need is in the header is returned by
-                   * png_get_IHDR.  If this fails, we can use 'png_error' to
+                   * png_get_IHDR, if this fails we can now use 'png_error' to
                   * signal the error and return control to the setjmp above.
                   */
                  if (png_get_IHDR(png_ptr, info_ptr, &width, &height,
-                                   &bit_depth, &color_type, &interlace_method,
+                     &bit_depth, &color_type, &interlace_method,
-                                   &compression_method, &filter_method))
+                     &compression_method, &filter_method))
                  {
                     int passes, pass;
@ -248,7 +242,7 @@ main(int argc, const char **argv)
                     /* Now read the pixels, pass-by-pass, row-by-row: */
                     png_start_read_image(png_ptr);
-                     for (pass = 0; pass < passes; ++pass)
+                     for (pass=0; pass<passes; ++pass)
                     {
                        png_uint_32 ystart, xstart, ystep, xstep;
                        png_uint_32 py;
@ -305,27 +299,19 @@ main(int argc, const char **argv)
                            * are, of course, much better ways of doing this
                            * than using a for loop:
                            */
-                           if (y == py)
+                           if (y == py) for (px = xstart, ppx = 0;
                              px < width; px += xstep, ++ppx) if (x == px)
                           {
-                              for (px = xstart, ppx = 0;
+                              /* 'ppx' is the index of the pixel in the row
-                                   px < width;
+                               * buffer.
-                                   px += xstep, ++ppx)
+                               */
-                              {
+                              print_pixel(png_ptr, info_ptr, row_tmp, ppx);
                                 if (x == px)
                                 {
                                    /* 'ppx' is the index of the pixel in the
                                     * row buffer.
                                     */
                                    print_pixel(png_ptr, info_ptr, row_tmp,
                                                ppx);
-                                    /* Now terminate the loops early - we have
+                              /* Now terminate the loops early - we have
-                                     * found and handled the required data.
+                               * found and handled the required data.
-                                     */
+                               */
-                                    goto pass_loop_end;
+                              goto pass_loop_end;
-                                 } /* x loop */
+                           } /* x loop */
                              }
                           }
                        } /* y loop */
                     } /* pass loop */
@ -337,6 +323,7 @@ main(int argc, const char **argv)
                  else
                     png_error(png_ptr, "pngpixel: png_get_IHDR failed");
               }
               else
@ -362,8 +349,7 @@ main(int argc, const char **argv)
            }
            else
-               fprintf(stderr,
+               fprintf(stderr, "pngpixel: out of memory allocating png_info\n");
                       "pngpixel: out of memory allocating png_info\n");
            png_destroy_read_struct(&png_ptr, NULL, NULL);
         }
@ -382,3 +368,4 @@ main(int argc, const char **argv)
   return result;
 }
 #endif /* READ && SEQUENTIAL_READ */
--- a/contrib/examples/pngtopng.c
+++ b/contrib/examples/pngtopng.c
@ -5,11 +5,13 @@
 * related or neighboring rights to this work.  This work is published from:
 * United States.
 *
 * Last changed in libpng 1.6.29 [March 16, 2017]
 *
 * Read a PNG and write it out in a fixed format, using the 'simplified API'
 * that was introduced in libpng-1.6.0.
 *
- * This sample code is just the code from 'example.c' with some error handling
+ * This sample code is just the code from the top of 'example.c' with some error
- * added.  See example.c in the top-level libpng directory for more comments.
+ * handling added.  See example.c for more comments.
 */
 #include <stddef.h>
 #include <stdlib.h>
@ -20,15 +22,10 @@
 * ensure the code picks up the local libpng implementation:
 */
 #include "../../png.h"
 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) && \
    defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
-#if !defined(PNG_SIMPLIFIED_READ_SUPPORTED) || \
+int main(int argc, const char **argv)
    !defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
 #error This program requires libpng supporting the simplified read/write API
 #endif
 int
 main(int argc, const char **argv)
 {
   int result = 1;
@ -53,22 +50,22 @@ main(int argc, const char **argv)
         if (buffer != NULL)
         {
-            if (png_image_finish_read(&image, NULL /*background*/, buffer,
+            if (png_image_finish_read(&image, NULL/*background*/, buffer,
-                                      0 /*row_stride*/, NULL /*colormap */))
+               0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
            {
-               if (png_image_write_to_file(
+               if (png_image_write_to_file(&image, argv[2],
-                      &image, argv[2], 0 /*convert_to_8bit*/, buffer,
+                  0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
-                      0 /*row_stride*/, NULL /*colormap*/))
+                  NULL/*colormap*/))
                  result = 0;
               else
                  fprintf(stderr, "pngtopng: write %s: %s\n", argv[2],
-                          image.message);
+                      image.message);
            }
            else
               fprintf(stderr, "pngtopng: read %s: %s\n", argv[1],
-                       image.message);
+                   image.message);
            free(buffer);
         }
@ -76,7 +73,7 @@ main(int argc, const char **argv)
         else
         {
            fprintf(stderr, "pngtopng: out of memory: %lu bytes\n",
-                    (unsigned long)PNG_IMAGE_SIZE(image));
+               (unsigned long)PNG_IMAGE_SIZE(image));
            /* This is the only place where a 'free' is required; libpng does
             * the cleanup on error and success, but in this case we couldn't
@ -98,3 +95,4 @@ main(int argc, const char **argv)
   return result;
 }
 #endif /* READ && WRITE */
--- a/contrib/examples/simpleover.c
+++ b/contrib/examples/simpleover.c
@ -6,9 +6,9 @@
 * United States.
 *
 * Read several PNG files, which should have an alpha channel or transparency
- * information, and composite them together to produce one or more 16-bit
+ * information, and composite them together to produce one or more 16-bit linear
- * linear RGBA intermediates.  This involves doing the 'over' compositing
+ * RGBA intermediates.  This involves doing the correct 'over' composition to
- * operation to combine the alpha channels and corresponding data.
+ * combine the alpha channels and corresponding data.
 *
 * Finally read an output (background) PNG using the 24-bit RGB format (the
 * PNG will be composited on green (#00ff00) by default if it has an alpha
@ -28,8 +28,8 @@
 * correctly.  Apart from the libpng Simplified API the only work done in here
 * is to combine multiple input PNG images into a single sprite; this involves
 * a Porter-Duff 'over' operation and the input PNG images may, as a result,
- * be regarded as being layered one on top of the other with the first
+ * be regarded as being layered one on top of the other with the first (leftmost
- * (leftmost on the command line) being at the bottom and the last on the top.
+ * on the command line) being at the bottom and the last on the top.
 */
 #include <stddef.h>
 #include <stdlib.h>
@ -44,61 +44,54 @@
 */
 #include "../../png.h"
-#if !defined(PNG_SIMPLIFIED_READ_SUPPORTED)
+#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
 #error This program requires libpng supporting the simplified read API
 #endif
 #define sprite_name_chars 15
-struct sprite
+struct sprite {
-{
+   FILE         *file;
-   FILE *file;
+   png_uint_16p  buffer;
-   png_uint_16p buffer;
+   unsigned int  width;
-   unsigned int width;
+   unsigned int  height;
-   unsigned int height;
+   char          name[sprite_name_chars+1];
   char name[sprite_name_chars + 1];
 };
 #if 0 /* div by 65535 test program */
 #include <math.h>
 #include <stdio.h>
-int
+int main(void) {
 main(void)
 {
   double err = 0;
   unsigned int xerr = 0;
   unsigned int r = 32769;
   unsigned int x = 0;
   do
   {
-      unsigned int t = x + (x >> 16) /*+ (x >> 31)*/ + r;
+      unsigned int x = 0;
      double v = x, errtest;
-      if (t < x)
+      do {
-      {
+         unsigned int t = x + (x >> 16) /*+ (x >> 31)*/ + r;
-         fprintf(stderr, "overflow: %u+%u -> %u\n", x, r, t);
+         double v = x, errtest;
         return 1;
      }
-      v /= 65535;
+         if (t < x) {
-      errtest = v;
+            fprintf(stderr, "overflow: %u+%u -> %u\n", x, r, t);
-      t >>= 16;
+            return 1;
      errtest -= t;
      if (errtest > err)
      {
         err = errtest;
         xerr = x;
         if (errtest >= .5)
         {
            fprintf(stderr, "error: %u/65535 = %f, not %u, error %f\n",
                    x, v, t, errtest);
            return 0;
         }
-      }
+
-   } while (++x <= 65535U * 65535U);
+         v /= 65535;
         errtest = v;
         t >>= 16;
         errtest -= t;
         if (errtest > err) {
            err = errtest;
            xerr = x;
            if (errtest >= .5) {
               fprintf(stderr, "error: %u/65535 = %f, not %u, error %f\n",
                     x, v, t, errtest);
               return 0;
            }
         }
      } while (++x <= 65535U*65535U);
   }
   printf("error %f @ %u\n", err, xerr);
@ -108,7 +101,7 @@ main(void)
 static void
 sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
-          png_imagep image, const png_uint_16 *buffer)
+   png_imagep image, const png_uint_16 *buffer)
 {
   /* This is where the Porter-Duff 'Over' operator is evaluated; change this
    * code to change the operator (this could be parameterized).  Any other
@ -119,8 +112,8 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
   /* Check for an x or y offset that pushes any part of the image beyond the
    * right or bottom of the sprite:
    */
-   if ((y_offset < 0 || /*SAFE*/ (unsigned)y_offset < sprite->height) &&
+   if ((y_offset < 0 || (unsigned)/*SAFE*/y_offset < sprite->height) &&
-       (x_offset < 0 || /*SAFE*/ (unsigned)x_offset < sprite->width))
+       (x_offset < 0 || (unsigned)/*SAFE*/x_offset < sprite->width))
   {
      unsigned int y = 0;
@ -137,7 +130,7 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
         do
         {
            /* In and out are RGBA values, so: */
-            const png_uint_16 *in_pixel = buffer + (y * image->width + x) * 4;
+            const png_uint_16 *in_pixel = buffer + (y * image->width + x)*4;
            png_uint_32 in_alpha = in_pixel[3];
            /* This is the optimized Porter-Duff 'Over' operation, when the
@ -146,10 +139,10 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
            if (in_alpha > 0)
            {
               png_uint_16 *out_pixel = sprite->buffer +
-                  ((y + y_offset) * sprite->width + (x + x_offset)) * 4;
+                  ((y+y_offset) * sprite->width + (x+x_offset))*4;
               /* This is the weight to apply to the output: */
-               in_alpha = 65535 - in_alpha;
+               in_alpha = 65535-in_alpha;
               if (in_alpha > 0)
               {
@ -166,9 +159,9 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
                   */
                  png_uint_32 tmp;
-#                 define compose(c) \
+#                 define compose(c)\
-                     tmp = out_pixel[c] * in_alpha; \
+                     tmp = out_pixel[c] * in_alpha;\
-                     tmp = (tmp + (tmp >> 16) + 32769) >> 16; \
+                     tmp = (tmp + (tmp >> 16) + 32769) >> 16;\
                     out_pixel[c] = tmp + in_pixel[c]
                  /* The following is very vectorizable... */
@ -179,15 +172,15 @@ sprite_op(const struct sprite *sprite, int x_offset, int y_offset,
               }
               else
-               {
+                  out_pixel[0] = in_pixel[0],
-                  out_pixel[0] = in_pixel[0];
+                  out_pixel[1] = in_pixel[1],
-                  out_pixel[1] = in_pixel[1];
+                  out_pixel[2] = in_pixel[2],
                  out_pixel[2] = in_pixel[2];
                  out_pixel[3] = in_pixel[3];
               }
            }
-         } while (++x < image->width);
+         }
-      } while (++y < image->height);
+         while (++x < image->width);
      }
      while (++y < image->height);
   }
 }
@ -231,8 +224,9 @@ create_sprite(struct sprite *sprite, int *argc, const char ***argv)
            if (buffer != NULL)
            {
-               if (png_image_finish_read(&image, NULL /*background*/, buffer,
+               if (png_image_finish_read(&image, NULL/*background*/, buffer,
-                                         0 /*row_stride*/, NULL /*colormap*/))
+                  0/*row_stride*/,
                  NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
               {
                  /* This is the place where the Porter-Duff 'Over' operator
                   * needs to be done by this code.  In fact, any image
@ -251,14 +245,14 @@ create_sprite(struct sprite *sprite, int *argc, const char ***argv)
               {
                  free(buffer);
                  fprintf(stderr, "simpleover: read %s: %s\n", (*argv)[0],
-                          image.message);
+                      image.message);
               }
            }
            else
            {
               fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
-                       (unsigned long)PNG_IMAGE_SIZE(image));
+                  (unsigned long)PNG_IMAGE_SIZE(image));
               /* png_image_free must be called if we abort the Simplified API
                * read because of a problem detected in this code.  If problems
@ -296,9 +290,8 @@ create_sprite(struct sprite *sprite, int *argc, const char ***argv)
      save.flags = PNG_IMAGE_FLAG_FAST;
      save.colormap_entries = 0;
-      if (png_image_write_to_stdio(&save, sprite->file, 1 /*convert_to_8_bit*/,
+      if (png_image_write_to_stdio(&save, sprite->file, 1/*convert_to_8_bit*/,
-                                   sprite->buffer, 0 /*row_stride*/,
+          sprite->buffer, 0/*row_stride*/, NULL/*colormap*/))
                                   NULL /*colormap*/))
      {
         /* Success; the buffer is no longer needed: */
         free(sprite->buffer);
@ -308,20 +301,19 @@ create_sprite(struct sprite *sprite, int *argc, const char ***argv)
      else
         fprintf(stderr, "simpleover: write sprite %s: %s\n", sprite->name,
-                 save.message);
+            save.message);
   }
   else
-      fprintf(stderr,
+      fprintf(stderr, "simpleover: sprite %s: could not allocate tmpfile: %s\n",
-              "simpleover: sprite %s: could not allocate tmpfile: %s\n",
+         sprite->name, strerror(errno));
              sprite->name, strerror(errno));
   return 0; /* fail */
 }
 static int
 add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
-           int *argc, const char ***argv)
+   int *argc, const char ***argv)
 {
   /* Given a --add argument naming this sprite, perform the operations listed
    * in the following arguments.  The arguments are expected to have the form
@ -342,13 +334,13 @@ add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
          * will fit.
          */
         if (x < 0 || y < 0 ||
-             /*SAFE*/ (unsigned)x >= output->width ||
+             (unsigned)/*SAFE*/x >= output->width ||
-             /*SAFE*/ (unsigned)y >= output->height ||
+             (unsigned)/*SAFE*/y >= output->height ||
-             sprite->width > output->width - x ||
+             sprite->width > output->width-x ||
-             sprite->height > output->height - y)
+             sprite->height > output->height-y)
         {
            fprintf(stderr, "simpleover: sprite %s @ (%d,%d) outside image\n",
-                    sprite->name, x, y);
+               sprite->name, x, y);
            /* Could just skip this, but for the moment it is an error */
            return 0; /* error */
         }
@ -367,10 +359,10 @@ add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
            {
               in.format = PNG_FORMAT_RGB; /* force compose */
-               if (png_image_finish_read(
+               if (png_image_finish_read(&in, NULL/*background*/,
-                      &in, NULL /*background*/,
+                  out_buf + (y*output->width + x)*3/*RGB*/,
-                      out_buf + (y * output->width + x) * 3 /*RGB*/,
+                  output->width*3/*row_stride*/,
-                      output->width * 3 /*row_stride*/, NULL /*colormap*/))
+                  NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP*/))
               {
                  ++*argv, --*argc;
                  continue;
@ -379,7 +371,7 @@ add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
            /* The read failed: */
            fprintf(stderr, "simpleover: add sprite %s: %s\n", sprite->name,
-                    in.message);
+                in.message);
            return 0; /* error */
         }
      }
@ -387,7 +379,7 @@ add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
      else
      {
         fprintf(stderr, "simpleover: --add='%s': invalid position %s\n",
-                 sprite->name, (*argv)[0]);
+               sprite->name, (*argv)[0]);
         return 0; /* error */
      }
   }
@ -397,10 +389,10 @@ add_sprite(png_imagep output, png_bytep out_buf, struct sprite *sprite,
 static int
 simpleover_process(png_imagep output, png_bytep out_buf, int argc,
-                   const char **argv)
+   const char **argv)
 {
   int result = 1; /* success */
-#  define csprites 10 /*limit*/
+#  define csprites 10/*limit*/
 #  define str(a) #a
   int nsprites = 0;
   struct sprite sprites[csprites];
@ -420,25 +412,23 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
            sprites[nsprites].width = sprites[nsprites].height = 0;
            sprites[nsprites].name[0] = 0;
-            n = sscanf(argv[0],
+            n = sscanf(argv[0], "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
-                       "--sprite=%u,%u,%" str(sprite_name_chars) "s%c",
+                &sprites[nsprites].width, &sprites[nsprites].height,
-                       &sprites[nsprites].width, &sprites[nsprites].height,
+                sprites[nsprites].name, &tombstone);
                       sprites[nsprites].name, &tombstone);
            if ((n == 2 || n == 3) &&
-                (sprites[nsprites].width > 0) &&
+                sprites[nsprites].width > 0 && sprites[nsprites].height > 0)
                (sprites[nsprites].height > 0))
            {
               size_t buf_size, tmp;
               /* Default a name if not given. */
               if (sprites[nsprites].name[0] == 0)
-                  sprintf(sprites[nsprites].name, "sprite-%d", nsprites + 1);
+                  sprintf(sprites[nsprites].name, "sprite-%d", nsprites+1);
               /* Allocate a buffer for the sprite and calculate the buffer
                * size:
                */
-               buf_size = sizeof(png_uint_16[4]);
+               buf_size = sizeof (png_uint_16 [4]);
               buf_size *= sprites[nsprites].width;
               buf_size *= sprites[nsprites].height;
@ -447,7 +437,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
               tmp /= sprites[nsprites].width;
               tmp /= sprites[nsprites].height;
-               if (tmp == sizeof(png_uint_16[4]))
+               if (tmp == sizeof (png_uint_16 [4]))
               {
                  sprites[nsprites].buffer = malloc(buf_size);
                  /* This buffer must be initialized to transparent: */
@ -458,7 +448,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
                     sprites[nsprites].file = NULL;
                     ++argv, --argc;
-                     if (create_sprite(sprites + nsprites++, &argc, &argv))
+                     if (create_sprite(sprites+nsprites++, &argc, &argv))
                     {
                        result = 1; /* still ok */
                        continue;
@ -476,8 +466,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
            else
            {
               fprintf(stderr, "simpleover: %s: invalid sprite (%u,%u)\n",
-                       argv[0],
+                  argv[0], sprites[nsprites].width, sprites[nsprites].height);
                       sprites[nsprites].width, sprites[nsprites].height);
               break;
            }
         }
@ -491,7 +480,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
      else if (strncmp(argv[0], "--add=", 6) == 0)
      {
-         const char *name = argv[0] + 6;
+         const char *name = argv[0]+6;
         int isprite = nsprites;
         ++argv, --argc;
@ -500,8 +489,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
         {
            if (strcmp(sprites[isprite].name, name) == 0)
            {
-               if (!add_sprite(output, out_buf, sprites + isprite,
+               if (!add_sprite(output, out_buf, sprites+isprite, &argc, &argv))
                               &argc, &argv))
                  goto out; /* error in add_sprite */
               break;
@ -510,8 +498,7 @@ simpleover_process(png_imagep output, png_bytep out_buf, int argc,
         if (isprite < 0) /* sprite not found */
         {
-            fprintf(stderr, "simpleover: --add='%s': sprite not found\n",
+            fprintf(stderr, "simpleover: --add='%s': sprite not found\n", name);
                    name);
            break;
         }
      }
@ -539,8 +526,7 @@ out:
   return result;
 }
-int
+int main(int argc, const char **argv)
 main(int argc, const char **argv)
 {
   int result = 1; /* default to fail */
@ -550,7 +536,7 @@ main(int argc, const char **argv)
      const char *output = NULL;
      png_image image;
-      if (argc > 2 && argv[2][0] != '-' /*an operation*/)
+      if (argc > 2 && argv[2][0] != '-'/*an operation*/)
      {
         output = argv[2];
         argi = 3;
@ -572,7 +558,7 @@ main(int argc, const char **argv)
            png_color background = {0, 0xff, 0}; /* fully saturated green */
            if (png_image_finish_read(&image, &background, buffer,
-                                      0 /*row_stride*/, NULL /*colormap*/))
+               0/*row_stride*/, NULL/*colormap for PNG_FORMAT_FLAG_COLORMAP */))
            {
               /* At this point png_image_finish_read has cleaned up the
                * allocated data in png_image, and only the buffer needs to be
@ -580,24 +566,22 @@ main(int argc, const char **argv)
                *
                * Perform the remaining operations:
                */
-               if (simpleover_process(&image, buffer,
+               if (simpleover_process(&image, buffer, argc-argi, argv+argi))
                                      argc - argi, argv + argi))
               {
                  /* Write the output: */
                  if ((output != NULL &&
-                       png_image_write_to_file(
+                       png_image_write_to_file(&image, output,
-                          &image, output, 0 /*convert_to_8bit*/, buffer,
+                        0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
-                          0 /*row_stride*/, NULL /*colormap*/)) ||
+                        NULL/*colormap*/)) ||
                      (output == NULL &&
-                       png_image_write_to_stdio(
+                       png_image_write_to_stdio(&image, stdout,
-                          &image, stdout, 0 /*convert_to_8bit*/, buffer,
+                        0/*convert_to_8bit*/, buffer, 0/*row_stride*/,
-                          0 /*row_stride*/, NULL /*colormap*/)))
+                        NULL/*colormap*/)))
                     result = 0;
                  else
                     fprintf(stderr, "simpleover: write %s: %s\n",
-                             output == NULL ? "stdout" : output,
+                        output == NULL ? "stdout" : output, image.message);
                             image.message);
               }
               /* else simpleover_process writes an error message */
@ -605,7 +589,7 @@ main(int argc, const char **argv)
            else
               fprintf(stderr, "simpleover: read %s: %s\n", argv[1],
-                       image.message);
+                   image.message);
            free(buffer);
         }
@ -613,7 +597,7 @@ main(int argc, const char **argv)
         else
         {
            fprintf(stderr, "simpleover: out of memory: %lu bytes\n",
-                    (unsigned long)PNG_IMAGE_SIZE(image));
+               (unsigned long)PNG_IMAGE_SIZE(image));
            /* This is the only place where a 'free' is required; libpng does
             * the cleanup on error and success, but in this case we couldn't
@ -633,8 +617,7 @@ main(int argc, const char **argv)
   else
   {
      /* Usage message */
-      fprintf(
+      fprintf(stderr,
         stderr,
         "simpleover: usage: simpleover background.png [output.png]\n"
         "  Output 'background.png' as a 24-bit RGB PNG file in 'output.png'\n"
         "   or, if not given, stdout.  'background.png' will be composited\n"
@ -645,13 +628,13 @@ main(int argc, const char **argv)
         "   --sprite=width,height,name {[--at=x,y] {sprite.png}}\n"
         "    Produce a transparent sprite of size (width,height) and with\n"
         "     name 'name'.\n"
-         "    For each sprite.png composite it is using a Porter-Duff 'Over'\n"
+         "    For each sprite.png composite it using a Porter-Duff 'Over'\n"
-         "     operation at offset (x,y) in the sprite, defaulting to (0,0).\n"
+         "     operation at offset (x,y) in the sprite (defaulting to (0,0)).\n"
         "     Input PNGs will be truncated to the area of the sprite.\n"
         "\n"
         "   --add='name' {x,y}\n"
         "    Optionally, before output, composite a sprite, 'name', which\n"
-         "     must have been previously produced using --sprite at each\n"
+         "     must have been previously produced using --sprite, at each\n"
         "     offset (x,y) in the output image.  Each sprite must fit\n"
         "     completely within the output image.\n"
         "\n"
@ -662,3 +645,4 @@ main(int argc, const char **argv)
   return result;
 }
 #endif /* SIMPLIFIED_READ */
--- a/contrib/gregbook/rpng-x.c
+++ b/contrib/gregbook/rpng-x.c
@ -21,7 +21,7 @@
    - 1.10:  added support for non-default visuals; fixed X pixel-conversion
    - 1.11:  added extra set of parentheses to png_jmpbuf() macro; fixed
              command-line parsing bug
-    - 1.12:  fixed some small X memory leaks (thanks to François Petitjean)
+    - 1.12:  fixed some small X memory leaks (thanks to François Petitjean)
    - 1.13:  fixed XFreeGC() crash bug (thanks to Patrick Welche)
    - 1.14:  added support for X resources (thanks to Gerhard Niklasch)
    - 2.00:  dual-licensed (added GNU GPL)
--- a/contrib/gregbook/rpng2-x.c
+++ b/contrib/gregbook/rpng2-x.c
@ -27,7 +27,7 @@
    - 1.11:  added -usleep option for demos; fixed command-line parsing bug
    - 1.12:  added -pause option for demos and testing
    - 1.20:  added runtime MMX-enabling/disabling and new -mmx* options
-    - 1.21:  fixed some small X memory leaks (thanks to François Petitjean)
+    - 1.21:  fixed some small X memory leaks (thanks to François Petitjean)
    - 1.22:  fixed XFreeGC() crash bug (thanks to Patrick Welche)
    - 1.23:  added -bgpat 0 mode (std white/gray checkerboard, 8x8 squares)
    - 1.30:  added -loop option for -bgpat (ifdef FEATURE_LOOP); fixed bpp =
--- a/contrib/libtests/gentests.sh
+++ b/contrib/libtests/gentests.sh
@ -2,6 +2,8 @@
 #
 # Copyright (c) 2013 John Cunningham Bowler
 #
 # Last changed in libpng 1.6.0 [February 14, 2013]
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
 # and license in png.h
--- a/Show More
+++ b/Show More
`@ -1,3 +1,4 @@`

	`This directory (contrib/examples) contains examples of libpng usage.`	`This directory (contrib/examples) contains examples of libpng usage.`

	`NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.`	`NO COPYRIGHT RIGHTS ARE CLAIMED TO ANY OF THE FILES IN THIS DIRECTORY.`