test versions of zlib-1.1.3-2 and libpng-1.0.7rc1-1

Charles S. Wilson cwilson@ece.gatech.edu
Sun Jun 18 12:00:00 GMT 2000

are available at


   pnggccrd.diff.gz (additional [non-functional] patch for asm stuff)

I've made a few cleanups and packaging changes to zlib and libpng (as
well as the obvious update to 1.0.7rc1 from 1.0.6c) I've also made those
two packages conform to the new cygwin 'standards' as it were:

o import-lib libfoo.dll.a  (not libfoo.a-dll)
o static-lib libfoo.a      (not libfoo.a-static)
o no funny symlink games
o cygwin-specific docs in /usr/doc/Cygwin/<package>-<version>.README
o generic docs in /usr/doc/<package>-<version>/*
o source archive has already had the cygwin specific patch applied

o cygwin specific README and patch are stored in the source archive,
under <top>/CYGWIN-PATCHES/* (although the patch has already been
applied to the archive itself).

o define -DZLIB_STATIC (and -DPNG_STATIC) to get the 'correct' #define's
when compiling a .o that will be linked statically -- as well as using
'-static' during the link step.

o no special -D options needed (or link options) to link with the dll.

These packages (libpng especially) are not yet ready for primetime. I'd
like feedback on several issues:

1) test reports (does it work for you? is building from the source
tarball painless?)

2) package structure (What do you think about CYGWIN-PATCHES?
Pre-applied patches in the source archives?).

3) help (additional patches?) in getting the dll (no asm) to pass the
pngtest tests.

4) help (additional patches?) in getting both static lib and dll *with*
pnggccrd.c to compile and pass the pngtest tests. I have already
developed a patch -- thanks to Marc Lehmann -- that allows pnggccrd.c to
compile, but the resulting library fails pngtest in both static and dll
versions. That patch is available as

The official libpng-1.0.7 should be coming out in about two weeks, and
I'd like to be in sync and ready to go for that. 

I've also realized that there are a few problems with even the
non-assember libpng dll. The pngtest linked with that dll fails some of
the tests. I'm not sure why, but am trying to track it down (help and
patches are always appreciated). It may be related to the recent change
in the cygwin-gcc specs file, which no longer defines WIN32 and friends.
Some of the #ifdefs in libpng may have depended on that...and need to be


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