On Fri, Nov 20, 2020 at 03:44:01PM -0700, Martin Sebor via Gcc-patches wrote:
> > So that likely means you are doing it too early.
>
> The bounds are added to attribute "arg spec" for each param in
> push_parm_decl. I think that's both as early and (except maybe
> in function definitions) as late as can be. After that point,
> the association between a VLA parameter and its most significant
> bound is lost.
If the most significant bound is lost, why don't you save in the attribute
early only the most significant bound before it is lost and for the other
bounds just refer to the SAVE_EXPRs in the FUNCTION_TYPE's TYPE_ARG_TYPES
ARRAY_TYPEs? And for function definitions, even the outermost bounds
aren't really lost, the FE for
int bar ();
int baz ();
int
foo (int n, int x[bar () + 4][baz () + 2])
{
return sizeof (x[0]);
}
emits all the side-effects, though not sure if it creates a SAVE_EXPR for
that. But for the definitions you really want to use the same SAVE_EXPR
as the function evaluates.
Jakub
