[FFmpeg-devel] [PATCH] configure: force erroring out in check_disable_warning() if an option doesn't exists

[Hendrik Leppkes]

On Fri, Oct 13, 2017 at 4:14 PM, James Almer <jamrial at gmail.com> wrote:
> On 10/12/2017 6:30 PM, James Almer wrote:
>> Should prevent some options from being added to cflags when they
>> don't exist and the compiler only warns about it.
>>
>> Signed-off-by: James Almer <jamrial at gmail.com>
>> ---
>> I figure this is safer than adding
>> -Werror=unused-command-line-argument -Werror=unknown-warning-option
>> as Ronald suggested.
>>
>>  configure | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/configure b/configure
>> index ade67a31bb..c7962665f1 100755
>> --- a/configure
>> +++ b/configure
>> @@ -6370,7 +6370,7 @@ fi
>>
>>  check_disable_warning(){
>>      warning_flag=-W${1#-Wno-}
>> -    test_cflags $warning_flag && add_cflags $1
>> +    test_cflags -Werror $warning_flag && add_cflags $1
>>  }
>>
>>  check_disable_warning -Wno-parentheses
>
> Ping. This or a similar solution has been annoying Clang users for some
> days now and should be part of the 3.4 release.

I wonder if a general -Werror is really "safer", do these tests really
execute without any other warnings, which might trigger a false
negative? We're not exactly making it compile a proper source file, so
it might warn about random things.

- Hendrik