Bug in PNG support of latest GNU and ESP Ghostscript

[Sven Moritz Hallberg]

GNU and ESP Ghostscript are not built with support for PNG devices, even
if so requested, because the configure script is lacking the definition of
PNG_DEVS. After I had added that, the build failed on gdevpng.c because
png_.h didn't include the libpng header at all, because the HAVE_PNG_H or
HAVE_LIBPNG_H macros are not set on the corresponding command line (in
gs.mak). I've added these flags to the variable PCF_ in gs.mak, I hope
that was the right way to do it. At least it works now.

This is my ChangeLog:

-----snip-----
2002-08-03  Sven Moritz Hallberg  <address@hidden>

        * configure.ac: Only mention Makefile in one AC_OUTPUT call.
        Add PNG_DEVS variable.
        src/gs.mak (PCF_): Add -D flags for HAVE_PNG_H and HAVE_LIBPNG_PNG_H.
-----snap-----

The diff is attached. It was made against ESP Ghostscript 7.05.3, but I
suspect it'll work unchanged for GNU Ghostscript as well. Notice that AFPL
Ghostscript, as far as I can see, should not be affected by this bug,
because the relevant parts appear to have been added by GNU.

To address@hidden: I hope you're the right person to send this patch
to, please incorporate it into the ebuild, because the missing PNG support
breaks the build for gstreamer (that's how I noticed it).


Greetings,
Sven Moritz