[PATCH V2] configure.ac: Fallback to older detection code if pkg-config can't find expat

[Peter Hutterer]

On Tue, Feb 03, 2015 at 12:32:22PM -0800, Bill Spitzak wrote:
> It looks like $(LIBS) is added by automake to every link, I can't figure out
> a way to stop it. Is this correct?

yes. the goal isn't to stop that, the goal is to keep everything that's not
a global requirement out of $LIBS :)

Cheers,
   Peter

> On 02/02/2015 10:46 PM, Peter Hutterer wrote:
> >On Mon, Feb 02, 2015 at 06:33:49PM -0800, Bill Spitzak wrote:
> >>
> >>
> >>On 02/02/2015 03:12 PM, sardemff7+wayland at sardemff7.net wrote:
> >>>On 2015-02-02 22:29, Bill Spitzak wrote:
> >>>>This paritally reverts commit a4afd90f9f0c27ed5f3f313b915c260673f8be34.
> >>>>
> >>>>On older expat versions (ie the one on Ubuntu 12.04) there is no
> >>>>pkg-config
> >>>>file, so fall back to the previous test for the header file when it
> >>>>fails.
> >>>>Test is slightly cleaned up from previous one.
> >>>>
> >>>>I could not use AC_SEARCH_LIBS as was suggested, as this leaves the
> >>>>switch
> >>>>in LIBS, not EXPAT_LIBS, and thus does not match the pkg-config results.
> >>>
> >>>Well, you can perfectly do that, especially since AC_CHECK_LIB does not
> >>>export EXPAT_LIBS either.
> >>
> >>I think I may need some expert autotools help. I was basing these changes on
> >>looking at what got put into the config.h and Makefile. If I used
> >>AC_SEARCH_LIBS it added "-lexpat" to LIBS. I could make it also add it to
> >>EXPAT_LIBS but I could not figure out a way to stop it from being added to
> >>LIBS.
> >
> >the usual process is (used to be?):
> >SAVE_LIBS="$LIBS"
> >AC_SEARCH_LIBS(....)
> >EXPAT_LIBS="$LIBS"
> >LIBS="$SAVE_LIBS"
> >
> >so you save the current state and restore it after it got mangled. we do
> >that for the rdp compositro CPPFLAGS already for example.