[Buildroot] [PATCH v4] cmake: don't use any header available in $(HOST_DIR)/usr/include

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Dear Fabio Porcedda,

On Sat,  7 Mar 2015 09:27:55 +0100, Fabio Porcedda wrote:
> The -I<dir> options added to CMAKE_C_FLAGS are passed to the compiler
> before the -I<dir> options of the cmake internal headers, so when the
> host-xz package was already built, a #include <lzma.h> directive loads
> the host-xz header instead of the cmake internal one.
> 
> Because we don't want to use any header avaiable in -I$(HOST_DIR)/usr/include,
> just get rid of the -I<dir> options in the HOST_CFLAGS.
> 
> Fix build failure:
>   make host-xz host-cmake
> 
> .../output/build/host-cmake-3.1.3/Utilities/cmliblzma/liblzma/common/block_buffer_decoder.c:17:1: error: conflicting types for ?lzma_block_buffer_decode?
>  lzma_block_buffer_decode(lzma_block *block, lzma_allocator *allocator,
>  ^
> In file included from /home/tetsuya/buildroot/br2/output/host/usr/include/lzma.h:296:0,
>                  from /home/tetsuya/buildroot/br2/output/build/host-cmake-3.1.3/Utilities/cmliblzma/liblzma/common/common.h:34,
>                  from /home/tetsuya/buildroot/br2/output/build/host-cmake-3.1.3/Utilities/cmliblzma/liblzma/common/block_decoder.h:16,
>                  from /home/tetsuya/buildroot/br2/output/build/host-cmake-3.1.3/Utilities/cmliblzma/liblzma/common/block_buffer_decoder.c:13:
> /home/tetsuya/buildroot/br2/output/host/usr/include/lzma/block.h:577:27: note: previous declaration of ?lzma_block_buffer_decode? was here
>  extern LZMA_API(lzma_ret) lzma_block_buffer_decode(
>                            ^
> Utilities/cmliblzma/CMakeFiles/cmliblzma.dir/build.make:261: recipe for target 'Utilities/cmliblzma/CMakeFiles/cmliblzma.dir/liblzma/common/block_buffer_decoder.c.o' failed
> make[3]: *** [Utilities/cmliblzma/CMakeFiles/cmliblzma.dir/liblzma/common/block_buffer_decoder.c.o] Error 1
> 
> Fixes:
> http://autobuild.buildroot.org/results/4edf6e169dc4a00d8a8bd16a86eba2316cbbd9e5
> http://autobuild.buildroot.org/results/a9ff38b22a36a2f8427d33085d3263a8cbfbd746
> http://autobuild.buildroot.org/results/ecaa0227249207b5450519832a193c1585ac8177
> 
> Signed-off-by: Fabio Porcedda <fabio.porcedda@gmail.com>
> Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
> Cc: Baruch Siach <baruch@tkos.co.il>
> Cc: Samuel Martin <s.martin49@gmail.com>

Thanks, I applied this patch, but I did some further changes:

    [Thomas:
     - simplify the sed expression. Instead of trying to remove '-I
       <something>' from $(HOST_CFLAGS), simply remove $(HOST_CPPFLAGS)
       from $(HOST_CFLAGS).
     - add the same logic for HOST_CXXFLAGS.]

See the final commit at
http://git.buildroot.net/buildroot/commit/?id=46bf8e8fd2428a733486ca192ba93588a7ac8d0e.

Thanks!

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com