2015-03-27 18:23 GMT+03:00 Jan Hubicka <hubi...@ucw.cz>:
> Hi,
> this patch fixes bug in symtab_node::verify_symtab_nodes pointed out by Ilya.
> The loop checking that there all comdats are linked by same_comdat_group was
> completely bogus. In addition it checked also external symbols that are
> currently not kept in groups. This bug was in mainline for months but
> apparently bounds checking is first code producing interesting comdat groups
> to
> trigger it.
>
> Ilya, can you please mind comitting the testcase? I am not quite sure where
> bounds checking should go offhand.
>
> Also concerning linking the comdat groups, currently all non-DECL_EXTERNAL
> symbols
> are linked and all !DECL_EXTERNAL symbols are non-linked. Bounds checking
> should
> follow this scheme. It may be cleaner to keep links for DECL_EXTERNAL, but
> lets
> deffer that for next stage1.
>
> Bootstrapped/regtested x86_64-linux. Committed.
>
> Honza
>
> Index: ChangeLog
> ===================================================================
> --- ChangeLog (revision 221735)
> +++ ChangeLog (working copy)
> @@ -1,5 +1,11 @@
> 2015-03-27 Jan Hubicka <hubi...@ucw.cz>
>
> + PR target/65531
> + * symtab.c (symtab_node::verify_symtab_nodes): Fix verification of
> + comdat groups.
> +
> +2015-03-27 Jan Hubicka <hubi...@ucw.cz>
> +
> PR ipa/65600
> * cgraph.c (cgraph_update_edges_for_call_stmt_node): Fix the case
> of optimized out indirect call.
> Index: symtab.c
> ===================================================================
> --- symtab.c (revision 221734)
> +++ symtab.c (working copy)
> @@ -1130,15 +1130,20 @@ symtab_node::verify_symtab_nodes (void)
> &existed);
> if (!existed)
> *entry = node;
> - else
> - for (s = (*entry)->same_comdat_group; s != NULL && s != node; s =
> s->same_comdat_group)
> + else if (!DECL_EXTERNAL (node->decl))
> + {
> + for (s = (*entry)->same_comdat_group; s != NULL && s != node;
> + s = s->same_comdat_group)
> + ;
With no if-statement in the loop body you need an additional exit
condition for a case when you reach the entry.
Thanks,
Ilya
> if (!s || s == *entry)
> {
> - error ("Two symbols with same comdat_group are not linked
> by the same_comdat_group list.");
> + error ("Two symbols with same comdat_group are not linked
> by "
> + "the same_comdat_group list.");
> (*entry)->debug ();
> node->debug ();
> internal_error ("symtab_node::verify failed");
> }
> + }
> }
> }
> }
