On Wed, Mar 09, 2016 at 04:20:24PM +0100, Marek Polacek wrote:
> --- gcc/testsuite/gcc.dg/nested-func-10.c
> +++ gcc/testsuite/gcc.dg/nested-func-10.c
> @@ -0,0 +1,49 @@
> +/* PR c/70093 */
> +/* { dg-do compile } */
> +/* { dg-options "" } */
> +
> +void
> +foo (int n)
> +{
> + struct S { int a[n]; };
> +
> + struct S __attribute__((noreturn))
> + fn (void)
> + {
> + __builtin_abort ();
> + }
> +
> + auto struct S __attribute__((noreturn))
> + fn2 (void)
> + {
> + __builtin_abort ();
> + }
> +
> + switch (n)
> + {
> + case 42:;
> + struct S x;
> + fn ();
> + fn2 ();
> + x = fn ();
> +
> + if (x.a[0] != 42)
> + __builtin_abort ();
> +
> + if (fn ().a[0] != 42)
> + __builtin_abort ();
> +
> + __typeof__ (fn ()) *p = &x;
> + if (p->a[0] != 42)
> + __builtin_abort ();
> +
> + if (fn2 ().a[0] != 42)
> + __builtin_abort ();
No, I meant:
switch (n)
{
struct S x;
case 1:
fn ();
break;
case 2:
fn2 ();
break;
case 3:
x = fn ();
if (x.a[0] != 42)
__builtin_abort ();
break;
case 4:
if (fn ().a[0] != 42)
__builtin_abort ();
break;
...
The reason is that anything after a noreturn call can be optimized away
shortly afterwards. Perhaps you want __attribute__((noinline, noclone)) on
the function too just in case (I know you haven't included -O*).
Otherwise LGTM.
Jakub
