Re: [PATCH 3/3] autoconf: correctly parse *_INCLUDES and *_LIB env vars

[Roger Pau Monne <roger.pau@citrix.com>]

Roger Pau Monne wrote:
> Ian Jackson wrote:
>> Roger Pau Monne writes ("[Xen-devel] [PATCH 3/3] autoconf: correctly parse *_INCLUDES and *_LIB env vars"):
>>> Parse those options correctly, since the "+=" operator is not valid.
>>> Also added CPPFLAGS, so headers checks don't give strange results.
>> ...
>>>    CFLAGS="$PREPEND_CFLAGS $CFLAGS $APPEND_CFLAGS"
>>> +CPPFLAGS="$CFLAGS"
>
> Without this I get the following (harmless but noisy) error:
>
> checking yajl/yajl_version.h usability... yes
> checking yajl/yajl_version.h presence... no
> configure: WARNING: yajl/yajl_version.h: accepted by the compiler,
> rejected by the preprocessor!
> configure: WARNING: yajl/yajl_version.h: proceeding with the compiler's
> result
>
>> Surely that can't be right.
>
>    From http://www.edwardrosten.com/code/autoconf/:
>
> "Just append stuff to CFLAGS (for the C compiler), CPPFLAGS (for the C
> preprocessor, C and C++ compilers), CXXFLAGS (for the C++ compiler) and
> LIBS (for the linker)."
>
> It seems like the preprocessor check uses CPPFLAGS instead of CFLAGS, so
> we have to set both.

Any news on this one?

Thanks, Roger.