Re: libpng issues

[Elias Mårtenson]

Hello Paul,

Your fix for this (e9ca57cfcbaf1a8dfc6bde5a2afd5f3c7b357cb1) causes the build to fail on Arch Linux.

Rolling back that change makes the build work again.

Here's the error:

make[2]: Leaving directory '/home/emartenson/src/emacs/admin/charsets'

make -C ../admin/unidata charscript.el

make[2]: Entering directory '/home/emartenson/src/emacs/admin/unidata'

make[2]: Nothing to be done for 'charscript.el'.

make[2]: Leaving directory '/home/emartenson/src/emacs/admin/unidata'

  CCLD     temacs

/bin/ld: image.o: undefined reference to symbol 'png_longjmp@@PNG16_0'

/usr/lib/libpng16.so.16: error adding symbols: DSO missing from command line

collect2: error: ld returned 1 exit status

make[1]: *** [Makefile:606: temacs] Error 1

make[1]: Leaving directory '/home/emartenson/src/emacs/src'

make: *** [Makefile:418: src] Error 2

Regards,

Elias

On 12 February 2018 at 10:45, Paul Eggert <address@hidden> wrote:

Werner LEMBERG wrote:

I've just been bitten by

   https://github.com/glennrp/libpng/issues/206

For this reason I suggest two improvements for the configure script of
emacs.

(1) Use `pkg-config' before `libpng-config' to detect libpng.

(2) If `libpng-config' is used, filter out `-L/usr/lib' and
     `-L/usr/lib64' (as suggested in issue #206).

Thanks, I installed the attached into master. It does (1), and as I understand it when (1) works then (2) is unnecessary. I'm hoping we don't have to do (2) as I worry that it might break things on some platforms.