OK.
Jason
On Tue, May 24, 2016 at 7:41 AM, Marek Polacek <pola...@redhat.com> wrote:
> Martin S. noticed that cc1plus bogusly warns on the following test. That's
> because I didn't realize that GIMPLE_BINDs might be nested in C++ so we need
> to
> look through them, and only then get the first statement in the seq.
>
> Bootstrapped/regtested on x86_64-linux, ok for trunk?
>
> 2016-05-24 Marek Polacek <pola...@redhat.com>
>
> PR c/71249
> * gimplify.c (gimplify_switch_expr): Look into the innermost lexical
> scope.
>
> * c-c++-common/Wswitch-unreachable-2.c: New test.
>
> diff --git gcc/gimplify.c gcc/gimplify.c
> index 6473544..5c5e9d6 100644
> --- gcc/gimplify.c
> +++ gcc/gimplify.c
> @@ -1605,8 +1605,9 @@ gimplify_switch_expr (tree *expr_p, gimple_seq *pre_p)
> && switch_body_seq != NULL)
> {
> gimple_seq seq = switch_body_seq;
> - if (gimple_code (switch_body_seq) == GIMPLE_BIND)
> - seq = gimple_bind_body (as_a <gbind *> (switch_body_seq));
> + /* Look into the innermost lexical scope. */
> + while (gimple_code (seq) == GIMPLE_BIND)
> + seq = gimple_bind_body (as_a <gbind *> (seq));
> gimple *stmt = gimple_seq_first_stmt (seq);
> enum gimple_code code = gimple_code (stmt);
> if (code != GIMPLE_LABEL && code != GIMPLE_TRY)
> diff --git gcc/testsuite/c-c++-common/Wswitch-unreachable-2.c
> gcc/testsuite/c-c++-common/Wswitch-unreachable-2.c
> index e69de29..8f57392 100644
> --- gcc/testsuite/c-c++-common/Wswitch-unreachable-2.c
> +++ gcc/testsuite/c-c++-common/Wswitch-unreachable-2.c
> @@ -0,0 +1,18 @@
> +/* PR c/71249 */
> +/* { dg-do compile } */
> +
> +int
> +f (int i)
> +{
> + switch (i)
> + {
> + {
> + int j;
> + foo:
> + return i; /* { dg-bogus "statement will never be executed" } */
> + };
> + case 3:
> + goto foo;
> + }
> + return i;
> +}
>
> Marek
