Re: error: Support the compiler's control flow analysis better (was: copy-file: Silence gcc warnings)

[Paul Eggert]

On 6/2/23 11:10, Bruno Haible wrote:
> +/* Avoid evaluating STATUS twice, if this is possible without making the
> +   "warning: this statement may fall through" reappear.  */
> +# if __OPTIMIZE__
> +#  define __gl_error_call(function, status, ...) \

That means semantics are different when optimizing; generally speaking 
optimization should affect only performance, not correctness.

How about changing this to use __builtin_constant_p instead of 
__OPTIMIZE__? I.e., use the comma expression if __builtin_constant_p 
(status), and use the statement expression otherwise.