RFA: new pass to warn on questionable uses of alloca() and VLAs

[Aldy Hernandez]

On 07/17/2016 11:52 AM, Manuel López-Ibáñez wrote:
> On 15/07/16 18:05, Aldy Hernandez wrote:
>
> +    case OPT_Walloca_larger_than_:
> +      if (!value)
> +    inform (loc, "-Walloca-larger-than=0 is meaningless");
> +      break;
> +
> +    case OPT_Wvla_larger_than_:
> +      if (!value)
> +    inform (loc, "-Wvla-larger-than=0 is meaningless");
> +      break;
> +
>
> We don't give similar notes for any of the other Wx-larger-than=
> options. If -Wvla-larger-than=0 suppresses a previous
> -Wvla-larger-than=, then it doesn't seem meaningless, but a useful thing
> to have.

I'm trying to avoid confusing users that may think that 
-Walloca-larger-than=0 means warn on any use of alloca.  That is what 
-Walloca is for.  But really, I don't care.  If you feel strongly about 
it, I can just remove the block of code.

Aldy