cwrappers config (.x11-buildlink) problem [was: libva-driver-vdpau strange configure error]

[tlaronde%polynum.com@localhost]

[Thanks to RVP for the hint to find the culprit!]

Problem: when trying to compile natively pkgsrc libva-driver-vdpau,
the configure exits with error since the header <vdpau/vdpau_x11.h> is
not found by the caller.

But it is present (in /usr/X11R7/include) and "-I/usr/X11R7/include" is
passed to "gcc".

If I invoke directly gcc, the same chunk of code succeeds.

The problem is with the cwrappers. "gcc" is not "true" gcc, but the PATH
manipulation leads to the use of work/.cwrapper/bin/gcc that is a 
symbolic link to the pkgsrc cwrapper in
/usr/pkg/libexec/cwrappers/cc-wrapper.

If this one is invoked (setting CWRAPPERS_CONFIG_DIR)---instead of i
"true" gcc---indeed the problem occurs.

This is because the wrapper uses a config (found in
work/.cwrapper/config) and in this config, if I understand correctly,
the "/usr/X11R7" prefix is replaced to point to the .x11-buildlink/
directory, where include/vdpau/vdpau_x11.h doesn't exist!

Does "vdpau/" subdir have to be added to the x11-buildlinks?

Note: It should be emphazized somewhere for debugging purposes that 
what is in config.log is not to be taken literaly because there is a 
lot of namespace manipulation going on in the background. And that the
programs are searched in some special place and that the arguments
may be rewritten.
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                     http://www.kergis.com/
                    http://kertex.kergis.com/
                       http://www.sbfa.fr/
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