[Mesa-dev] [PATCH 1/5] mesa: add STATIC_ASSERT() macro for compile-time assertions

[Eric Anholt]

On Mon, 28 Nov 2011 18:15:27 -0700, Brian Paul <brianp at vmware.com> wrote:
> This can be used to check that tables have the right number of entries,
> etc. at compile-time.  This will hopefully catch things that are missed
> if particular drivers aren't tested, for example.

I've always wanted to go dig up one of these and start using it.  Thanks!

> ---
>  src/mesa/main/compiler.h |   11 +++++++++++
>  1 files changed, 11 insertions(+), 0 deletions(-)
> 
> diff --git a/src/mesa/main/compiler.h b/src/mesa/main/compiler.h
> index 921e302..96e24e4 100644
> --- a/src/mesa/main/compiler.h
> +++ b/src/mesa/main/compiler.h
> @@ -310,6 +310,17 @@ static INLINE GLuint CPU_TO_LE32(GLuint x)
>  #endif
>  #endif
>  
> +
> +/**
> + * Static (compile-time) assertion.
> + * Basically, use COND to dimension an array.  If COND is false/zero the
> + * array size will be -1 and we'll get a compilation error.
> + */
> +#define JOIN(x, y) x##y
> +#define STATIC_ASSERT_LINE(COND, LINE) do { typedef int JOIN(static_assertion_failed_at_line_,LINE)[(!!(COND))*2-1]; } while (0)
> +#define STATIC_ASSERT(COND)  STATIC_ASSERT_LINE(COND, __LINE__)

Looks like STATIC_ASSERT_LINE could get linewrapped, right?
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 197 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/mesa-dev/attachments/20111128/6a66e974/attachment.pgp>