On Wed, 5 Feb 2014, Jakub Jelinek wrote:
> Hi!
>
> As the testcase shows, invalid use of noreturn attribute (which we diagnose)
> can result in in empty bb with no successors. This patch fixes
> cleanup_empty_eh not to ICE on these.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
Ok.
Thanks,
Richard.
> 2014-02-04 Jakub Jelinek <ja...@redhat.com>
>
> PR middle-end/57499
> * tree-eh.c (cleanup_empty_eh): Bail out on totally empty
> bb with no successors.
>
> * g++.dg/torture/pr57499.C: New test.
>
> --- gcc/tree-eh.c.jj 2014-01-31 22:22:09.000000000 +0100
> +++ gcc/tree-eh.c 2014-02-04 12:35:05.611066852 +0100
> @@ -4396,8 +4396,11 @@ cleanup_empty_eh (eh_landing_pad lp)
> /* If the block is totally empty, look for more unsplitting cases. */
> if (gsi_end_p (gsi))
> {
> - /* For the degenerate case of an infinite loop bail out. */
> - if (infinite_empty_loop_p (e_out))
> + /* For the degenerate case of an infinite loop bail out.
> + If bb has no successors and is totally empty, which can happen e.g.
> + because of incorrect noreturn attribute, bail out too. */
> + if (e_out == NULL
> + || infinite_empty_loop_p (e_out))
> return ret;
>
> return ret | cleanup_empty_eh_unsplit (bb, e_out, lp);
> --- gcc/testsuite/g++.dg/torture/pr57499.C.jj 2014-02-04 12:52:10.241846755
> +0100
> +++ gcc/testsuite/g++.dg/torture/pr57499.C 2014-02-04 12:51:51.000000000
> +0100
> @@ -0,0 +1,14 @@
> +// PR middle-end/57499
> +// { dg-do compile }
> +
> +struct S
> +{
> + ~S () __attribute__ ((noreturn)) {} // { dg-warning "function does return"
> }
> +};
> +
> +void
> +foo ()
> +{
> + S s;
> + throw 1;
> +}
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746
GF: Jeff Hawn, Jennifer Guild, Felix Imend"orffer
