[Mesa-dev] [PATCH 1/4] scons: Move fallback HAVE_* definitions to headers.

[Jose Fonseca]

On 22/04/16 15:03, Roland Scheidegger wrote:
> Am 22.04.2016 um 10:35 schrieb Jose Fonseca:
>> These were being defined in SCons, but it's not practical:
>>
>> - we actually need to include Gallium headers from external source trees, with
>> completely disjoint build infrastructure, and it's unsustainable to
>> replicate the HAVE_xxx checks or even hard-coded defines across
>> everywhere.
>>
>> - checking compiler version via command line doesn't really work due to
>>    Clang essentially being like a cameleon which can fake either GCC or
>>    MSVC
>>
>> There's no change for autoconf.
>> ---
>>   include/c99_compat.h | 44 ++++++++++++++++++++++++++++++++++++++++++++
>>   scons/gallium.py     | 48 +++++-------------------------------------------
>>   src/util/macros.h    |  2 ++
>>   3 files changed, 51 insertions(+), 43 deletions(-)
>>
>> diff --git a/include/c99_compat.h b/include/c99_compat.h
>> index b55ad9c..bfe655b 100644
>> --- a/include/c99_compat.h
>> +++ b/include/c99_compat.h
>> @@ -135,4 +135,48 @@ test_c99_compat_h(const void * restrict a,
>>   #endif
>>
>>
>> +/* Fallback definitions, for build systems other than autoconfig which don't
>> + * auto-detect these things. */
>> +#ifdef HAVE_NO_AUTOCONF
>> +
>> +#  ifndef _WIN32
>> +#    define HAVE_PTHREAD
>> +#    define HAVE_POSIX_MEMALIGN
>> +#  endif
>> +
>> +#  ifdef __GNUC__
>> +#    if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 2)
>> +#      error "GCC version 4.2 or higher required"
>> +#    endif
>> +
>> +     /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Other-Builtins.html */
>> +#    define HAVE___BUILTIN_CLZ 1
>> +#    define HAVE___BUILTIN_CLZLL 1
>> +#    define HAVE___BUILTIN_CTZ 1
>> +#    define HAVE___BUILTIN_EXPECT 1
>> +#    define HAVE___BUILTIN_FFS 1
>> +#    define HAVE___BUILTIN_FFSLL 1
>> +#    define HAVE___BUILTIN_POPCOUNT 1
>> +#    define HAVE___BUILTIN_POPCOUNTLL 1
>> +     /* https://gcc.gnu.org/onlinedocs/gcc-4.2.4/gcc/Function-Attributes.html */
>> +#    define HAVE_FUNC_ATTRIBUTE_FLATTEN 1
>> +#    define HAVE_FUNC_ATTRIBUTE_UNUSED 1
>> +#    define HAVE_FUNC_ATTRIBUTE_FORMAT 1
>> +#    define HAVE_FUNC_ATTRIBUTE_PACKED 1
>> +
>> +#    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
>> +       /* https://gcc.gnu.org/onlinedocs/gcc-4.3.6/gcc/Other-Builtins.html */
>> +#      define HAVE___BUILTIN_BSWAP32 1
>> +#      define HAVE___BUILTIN_BSWAP64 1
>> +#    endif
>> +
>> +#    if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
>> +#      define HAVE___BUILTIN_UNREACHABLE 1
>> +#    endif
>> +
>> +#  endif /* __GNUC__ */
>> +
>> +#endif /* !HAVE_AUTOCONF */
>> +
>> +
>>   #endif /* _C99_COMPAT_H_ */
> Is that the right file for putting them in?

I could put them in a seperate header.

The ideal would be for autotools to generate "mesa_config.h" somewhere 
with all the #defines instead of passing -DHAVE foo in the command line. 
  In that case, Scons would use a handwritten mesa_config.h with the the 
above definitions, and would use it by merely adding it's include path.

But until that happens it doesn't make much difference.

> But either way, for the series:
> Reviewed-by: Roland Scheidegger <sroland at vmware.com>

Thanks.

Jose