http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60092
--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Andreas Schwab from comment #11)
> If a function is not allowed to change errno this must be explicitly
> documented.
That means
Index: gcc/tree-ssa-alias.c
===================================================================
--- gcc/tree-ssa-alias.c.orig 2014-02-06 15:43:42.138266256 +0100
+++ gcc/tree-ssa-alias.c 2014-02-06 15:43:33.046266882 +0100
@@ -1847,7 +1847,9 @@ call_may_clobber_ref_p_1 (gimple call, a
ao_ref dref;
ao_ref_init_from_ptr_and_size (&dref, ptrptr,
TYPE_SIZE_UNIT (ptr_type_node));
- return refs_may_alias_p_1 (&dref, ref, false);
+ return (refs_may_alias_p_1 (&dref, ref, false)
+ || (flag_errno_math
+ && targetm.ref_may_alias_errno (ref)));
}
/* Freeing memory kills the pointed-to memory. More importantly
the call has to serve as a barrier for moving loads and stores
is necessary.
