Comment author: @xavierleroy

It's a great idea to try pkg-config first. A proposal for a patch would be very welcome.

Comment author: pveber

I've attached a first shot (configure.x11.patch). I tried to keep modifications to the minimum.

Comment author: gerd

Looking at Philippe's patch. On my system the two pkg-config commands output the empty string. I think this is not properly handled: "test -f $dir/X11/X.h" does not work when $dir is empty. Same with the library test. I think the proper way to go is to just believe pkg-config when it exits with code 0, and not testing the existence of files. A meaningful test would be compiling a test program with the flags.

Also, we should be prepared that pkg-config is not available, and just use the old code then.

Philippe: I don't understand the sed.

Comment author: gerd

Attached my shot at the problem: configure-x11-gerd.diff

Comment author: @xavierleroy

Gerd's patch looks good to me. Thanks. To be reviewed and applied.

Comment author: @lefessan

The patch requires some work, to be applied to trunk (it is based on 3.12.1).

In the meantime, maybe some developers could try it on their systems, to be sure it does not break working configuration.

I tested it on Linux amd64/Ubuntu 10.10 Maverick, and it worked for me.

Comment author: @damiendoligez

There is an obvious typo in Gerd's patch: if pkg-config returns without error, then it sets the variable "X11_include" with a capital X, a variable that is not used anywhere else.

So I'm surprised it works on Ubuntu.

Comment author: mehdi

"pkg-config --cflags x11" returns an empty string on Debian Wheezy and Ubuntu 11.xx (and probably 10.xx too… I didn't test other versions). So that might explain it.

Comment author: @damiendoligez

I have adapted Gerd's patch to trunk and removed the bug. Tested on MacOSX 10.6. It selects macports' X11 library in preference to Apple's but that works just as well.

Tested also on 32-bit Ubuntu 11.04.
And also on 32-bit Windows7/cygwin.

Committed to trunk [3.13.0] (commit 12110)