[FFmpeg-devel] [PATCH] configure: Silence Xcode warnings about duplicate libraries

[Martin Storsjö]

On Sun, 13 Oct 2024, Michael Niedermayer wrote:

> On Wed, Sep 25, 2024 at 03:16:40PM +0300, Martin Storsjö wrote:
>> Since Xcode 15, macOS developer tools use a new linker. The new
>> linker by default warns for duplicate -l options. As this is a
>> known and expected thing, not to be considered an issue, ask for
>> the warning to be silenced.
>>
>> This silences linker warnings like this:
>>
>>     ld: warning: ignoring duplicate libraries: '-lc++', '-lcrypto', '-lm', '-logg', '-lpthread', '-lssl', '-lvorbis', '-lvpx', '-lz'
>>
>> The linker can also warn about duplicate -rpath options, and there's
>> currently no option to silence those warnings.
>> ---
>>  configure | 1 +
>>  1 file changed, 1 insertion(+)
>>
>> diff --git a/configure b/configure
>> index d77a55b653..a450b3c8d8 100755
>> --- a/configure
>> +++ b/configure
>> @@ -6480,6 +6480,7 @@ check_cc intrinsics_sse2 emmintrin.h "__m128i test = _mm_setzero_si128()"
>>
>>  check_ldflags -Wl,--as-needed
>>  check_ldflags -Wl,-z,noexecstack
>> +check_ldflags -Wl,-no_warn_duplicate_libraries
>>
>>  if ! disabled network; then
>>      check_func getaddrinfo $network_extralibs
>
> this causes problems with build and
> also there is a:
> -rwxr-x---   1 michael michael  317432 Oct 13 21:39 _warn_duplicate_libraries*
>
> also if i replace this by -Wl,-no_warn_catgirl i get
>
> -rwxr-x---   1 michael michael 178629347 Oct 13 21:45 _warn_catgirl
>
> with no warning

That's odd...

What version of ld is this using (is it a distro provided mingw toolchain 
- what distro/version in that case)?

I can reproduce this, that the option does get accepted with binutils 
2.25, but not with binutils 2.38.

// Martin