diff --git a/.appveyor.yml b/.appveyor.yml
index 3347886c3..07e7bc483 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -40,11 +40,9 @@ environment:
       CI_CC: x86_64-w64-mingw32-gcc
     - TOOLCHAIN: msys2
       AUTOMATION: legacy
-      CI_LEGACY_MAKEFILES: scripts/makefile.gcc scripts/makefile.msys
       CI_CC: i686-w64-mingw32-gcc
     - TOOLCHAIN: msys2
       AUTOMATION: legacy
-      CI_LEGACY_MAKEFILES: scripts/makefile.gcc scripts/makefile.msys
       CI_CC: x86_64-w64-mingw32-gcc
 
 install:
@@ -60,6 +58,7 @@ before_build:
   - 'set CI_CMAKE_BUILD_FLAGS=--parallel 2'
   - 'set CI_CTEST_FLAGS=--parallel 2'
   - 'set CI_MAKE_FLAGS=-j2'
+  - 'set CI_LEGACY_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%\scripts\ci_cmake.sh"'
diff --git a/.travis.yml b/.travis.yml
index 2694e3289..e2b07eac0 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -35,7 +35,7 @@ before_script:
   - 'export CI_CTEST_FLAGS="--parallel 2"'
   - 'export CI_MAKE_FLAGS=-j2'
   - 'export CI_CC=$TRAVIS_COMPILER'
-  - 'export CI_LEGACY_MAKEFILES="scripts/makefile.$TRAVIS_COMPILER"'
+  - 'export CI_LEGACY_MAKEFILES="scripts/makefile.$TRAVIS_COMPILER scripts/makefile.std"'
 
 script:
   - './scripts/ci_$AUTOMATION.sh'
diff --git a/scripts/makefile.std b/scripts/makefile.std
index 2f4871df9..34c8770f0 100644
--- a/scripts/makefile.std
+++ b/scripts/makefile.std
@@ -1,4 +1,5 @@
 # makefile for libpng
+# Copyright (C) 2020 Cosmin Truta
 # Copyright (C) 2002, 2006, 2014 Glenn Randers-Pehrson
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 #
@@ -28,6 +29,8 @@ ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
 CC = cc
+CPP = $(CC) -E
+LD = $(CC)
 AR_RC = ar rc
 MKDIR_P = mkdir
 LN_SF = ln -sf
@@ -36,22 +39,22 @@ CP = cp
 RM_F = rm -f
 AWK = awk
 SED = sed
-CPP = $(CC) -E
 ECHO = echo
 
 DFNFLAGS = # DFNFLAGS contains -D options to use in the libpng build
 DFA_EXTRA = # extra files that can be used to control configuration
 CPPFLAGS = -I$(ZLIBINC) # -DPNG_DEBUG=5
 CFLAGS = -O # -g
-LDFLAGS = -L. -L$(ZLIBLIB) -lpng -lz -lm
+LDFLAGS = -L$(ZLIBLIB)
+LIBS = -lz -lm
 
 # Pre-built configuration
 # See scripts/pnglibconf.mak for more options
 PNGLIBCONF_H_PREBUILT = scripts/pnglibconf.h.prebuilt
 
-OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-	pngwtran.o pngmem.o pngerror.o pngpread.o
+OBJS = png.o pngerror.o pngget.o pngmem.o pngpread.o \
+       pngread.o pngrio.o pngrtran.o pngrutil.o pngset.o \
+       pngtrans.o pngwio.o pngwrite.o pngwtran.o pngwutil.o
 
 .c.o:
 	$(CC) -c $(CPPFLAGS) $(CFLAGS) -o $@ $<
@@ -79,11 +82,11 @@ pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa
 	mv pnglibconf.tmp $@
 
 libpng.a: $(OBJS)
-	$(AR_RC) $@  $(OBJS)
+	$(AR_RC) $@ $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+	$(LD) $(LDFLAGS) -o $@ pngtest.o libpng.a $(LIBS)
 
 test: pngtest
 	./pngtest
@@ -106,8 +109,8 @@ install: libpng.a pnglibconf.h
 	chmod 644 $(DESTDIR)$(LIBPATH)/libpng.a
 
 clean:
-	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h pnglibconf.c \
-	pnglibconf.out
+	$(RM_F) *.o libpng.a pngtest pngout.png pnglibconf.h
+	$(RM_F) pnglibconf.c pnglibconf.dfn pnglibconf.out pnglibconf.pre
 
 DOCS = ANNOUNCE CHANGES INSTALL KNOWNBUG LICENSE README TODO
 writelock:
@@ -115,20 +118,20 @@ writelock:
 
 # DO NOT DELETE THIS LINE -- make depend depends on it.
 
-png.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+png.o:      png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngerror.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngrio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngwio.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngmem.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngset.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngget.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngget.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngmem.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngpread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
-pngread.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngread.o:  png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngrio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngrutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngset.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngtrans.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
+pngwio.o:   png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwrite.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwtran.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 pngwutil.o: png.h pngconf.h pnglibconf.h pngpriv.h pngstruct.h pnginfo.h pngdebug.h
 
-pngtest.o: png.h pngconf.h pnglibconf.h
+pngtest.o:  png.h pngconf.h pnglibconf.h