[Mesa-dev] [PATCH] meson: do not search for needless deps

[Erik Faye-Lund]

On Thu, Oct 26, 2017 at 11:49 AM, Gert Wollny <gw.fossdev at gmail.com> wrote:
>
> Am Mittwoch, den 25.10.2017, 10:24 +0200 schrieb Erik Faye-Lund:
>> If we don't want to use these deps, there's no good reason to search
>> for them in the first place. This should shave a bit of time for the
>> initial build.
>> ---
>>
>> This would be a way of dealing with Gert's suggestion. Goes on top
>> of the previous patch.
>>
>> Thoughts?
>>
>>  meson.build | 20 ++++++++++++++------
>>  1 file changed, 14 insertions(+), 6 deletions(-)
>>
>> diff --git a/meson.build b/meson.build
>> index e842bb1652..201956c4c8 100644
>> --- a/meson.build
>> +++ b/meson.build
>> @@ -666,9 +666,13 @@ if with_glvnd
>>  endif
>>
>>  # TODO: make this conditional
>> -dep_valgrind = dependency('valgrind', required : false)
>> -if dep_valgrind.found() and with_valgrind
>> -  pre_args += '-DHAVE_VALGRIND'
>> +if with_valgrind
>> +  dep_valgrind = dependency('valgrind', required : false)
>> +  if dep_valgrind.found()
>> +    pre_args += '-DHAVE_VALGRIND'
>> +  endif
>> +else
>> +  dep_valgrind = []
>>  endif
>>
>>  # pthread stubs. Lets not and say we didn't
>> @@ -681,9 +685,13 @@ dep_selinux = []
>>
>>  # TODO: llvm-prefix and llvm-shared-libs
>>
>> -dep_unwind = dependency('libunwind', required : false)
>> -if dep_unwind.found() and with_libunwind
>> -  pre_args += '-DHAVE_LIBUNWIND'
>> +if with_libunwind
>> +  dep_unwind = dependency('libunwind', required : false)
>> +  if dep_unwind.found()
>> +    pre_args += '-DHAVE_LIBUNWIND'
>> +  endif
>> +else
>> +  dep_unwind = []
>>  endif
>>
>>  # TODO: flags for opengl, gles, dri
>
> Obviously, I like this more, but after reviewing what is done with the
> autotools, I think it would be preferable if meson would do the same
> i.e. with autotools
>
>   --enable-libunwind=no -> don't use libunwind
>   --enable-libunwind=yes -> require libunwind
>
> and if not given, then use it if available. The "force using libunwind"
> option is currently missing.
>
> I don't know yet how to use meson properly, but I guess one could
> achieve this  by something like (put in the apropriate files):
>
> option('with_libunwind',
>         type : 'combo',
>         choices : ['auto', 'yes', 'no'])
>
> if with_libunwind != 'no'
>   dep_unwind = dependency('libunwind',
>                            required : with_libunwind == 'yes')
>   if dep_unwind.found()
>     pre_args += '-DHAVE_LIBUNWIND'
>   endif
> else
>   dep_unwind = []
> endif
>

Yeah, that would probably be even nicer, as it would allow someone to
*ensure* they're using libunwind / valgrind.