[FFmpeg-devel] [PATCH 1/3] configure: use c++11 and fallback to c++0x for c++ files

[James Almer]

On 3/25/2017 8:51 PM, Marton Balint wrote:
> Needed for the C+11 atomics. Also change add_cxxflags to check_cxxflags.
> 
> Signed-off-by: Marton Balint <cus at passwd.hu>
> ---
>  configure | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/configure b/configure
> index c1aeb6e..6823894 100755
> --- a/configure
> +++ b/configure
> @@ -4648,7 +4648,7 @@ fi
>  
>  add_cppflags -D_ISOC99_SOURCE
>  add_cxxflags -D__STDC_CONSTANT_MACROS
> -add_cxxflags -std=c++98
> +check_cxxflags -std=c++11 || check_cxxflags -std=c++0x

Do compilers that support setting --std=c++0x (Old provisional name for C++11)
have actual support for std::atomic? They have by definition experimental and
incomplete support for the standard in question.
Maybe an actual check for it would be needed if --std=c++11 isn't available.

>  
>  # some compilers silently accept -std=c11, so we also need to check that the
>  # version macro is defined properly
>