This reverts commit 70fda1837d5de802ce5f7e04be239192b6a74d92.
Fixing Clang on Windows is important. However, in the previous fix,
the name of the compiled libpng library file was changed, incorrectly,
on all platforms except Windows. A proper fix will follow up.
Fix a build error that occurs with the Ninja code generator and the
Clang compiler on Windows:
ninja: error: build.ninja: multiple rules generate png16.lib
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Building the version script test executable may fail in the link step
with GNU ld as linker like this:
ld: final link failed: Nonrepresentable section on output
Building the test excutable with CMAKE_SHARED_LIBRARY_C_FLAGS makes the
test succeed with GNU ld since this adds -fpic/-fPIC.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Fix the issue of a
clang: error: no such file or directory: 'x86_64'
error on building universal binaries on macOS.
It is also necessary to specify:
-DCMAKE_C_FLAGS="-DPNG_ARM_NEON_OPT=0"
Example CMake command:
cmake -S libpng \
-B build_libpng \
-DCMAKE_OSX_ARCHITECTURES="arm64;x86_64" \
-DCMAKE_C_FLAGS="-DPNG_ARM_NEON_OPT=0"
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
This matches the configure script - unless the user has requested
anything, no hardware optimizations are autoenabled.
Defaulting to "check" is brittle (that configuration is deprecated
and poorly supported) - and for configurations where it would
make sense (where NEON isn't universally enabled in the compiler)
it didn't end up setting ARM_NEON_OPT to 1 in pnglibconf.h anyway.
This fixes default builds with cmake for iOS and Windows on armv7,
where NEON is universally available (but there's no runtime check
implemented) - but actually using NEON on this architecture
requires explicitly opting in to it when configuring, just like
with the configure script.
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
The ld version script should not be generated on Android.
Co-authored-by: Volker Krause <vkrause@kde.org>
Co-authored-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
The issue is that, by default, Git for Windows checks out text files
with CRLF line endings. This is a problem for awk, which is expecting
Unix-style LF line endings. When cloning on Windows and attempting to
compile on WSL, Mingw or Cygwin, there may be an error from awk.
The fix is to leverage CMake's ability to configure a file and perform
EOL conversions. We copy the awk scripts from the source directory to
the build directory. This portable method ensures they have LF endings,
and the build logic is updated to use the build directory version.
Intentionally avoiding .gitattributes to avoid setting precedent.
Co-authored-by: Christopher Sean Morrison <brlcad@gmail.com>
Co-authored-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Generated files depend on other generated files, and this previously
resulted in the same custom command output being a dependency of
multiple other custom commands without a shared custom targets.
Adds a top-level target for each generated file and ensures that
commands that depend on generated files also depend on the corresponding
custom targets.
Per CMake documentation:
> Do not list the output in more than one independent target
> that may build in parallel or the two instances of the rule
> may conflict (instead use add_custom_target to drive the command
> and make the other targets depend on that one).
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
Use standard CMake variables in the install target.
Reformulate comments and error messages.
Move all CMake keywords in front of their arguments.
Fix indentation.
Add the CMake option PNG_EXECUTABLES (on by default) in order to
allow or disallow the building of non-essential executable programs
associated with libpng.
Contributed-by: Alex Gaynor <alex.gaynor@gmail.com>
Contributed-by: Cosmin Truta <ctruta@gmail.com>
Signed-off-by: Cosmin Truta <ctruta@gmail.com>
When building with Emscripten, linkage to libm is neither required
nor working. As find_library will fail, M_LIBRARY will be set to
NOTFOUND and the build would fail later. The build works just fine
without libm linkage.
Although CMake version 3.0.2 was previously required, the policies
CMP0053 and CMP0054, introduced only in CMake version 3.1 and used
in this CMakeLists file, can have surprising effects under an older
CMake version.
Simplify the CMakeLists file by setting the global policy version
to 3.1, and remove the specific policy settings.
As an added bonus, remove the vestigial workarounds for all ancient
CMake versions.
Only use libm on Unix and Unix-like systems, except for Apple (where
it's unnecessary), and BeOS and Haiku (where it's unavailable).
Avoid searching for libm at explicit locations. They may be incorrect,
especially for cross-platform builds.
