[Mesa-dev] [PATCH 1/2] mesa: Add unreachable macro.

[Matt Turner]

On Mon, Nov 4, 2013 at 4:43 PM, Matt Turner <mattst88 at gmail.com> wrote:
> ---
>  src/mesa/main/compiler.h | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/src/mesa/main/compiler.h b/src/mesa/main/compiler.h
> index 61ce5db..6a25bf5 100644
> --- a/src/mesa/main/compiler.h
> +++ b/src/mesa/main/compiler.h
> @@ -252,6 +252,21 @@ static INLINE GLuint CPU_TO_LE32(GLuint x)
>        (void) sizeof(char [1 - 2*!(COND)]); \
>     } while (0)
>
> +/**
> + * Unreachable macro. Useful for suppressing "control reaches end of non-void
> + * function" warnings.
> + */
> +#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 5
> +#define unreachable __builtin_unreachable()
> +#elif (defined(__clang__) && defined(__has_builtin))
> +# if __has_builtin(__builtin_unreachable)
> +#  define unreachable __builtin_unreachable()
> +# endif
> +#endif
> +
> +#ifndef unreachable
> +#define unreachable
> +#endif
>
>  #if (__GNUC__ >= 3)
>  #define PRINTFLIKE(f, a) __attribute__ ((format(__printf__, f, a)))
> --
> 1.8.3.2
>

I'm actually going to change these to 'unreachable()' so it looks less funny.