On 05/13/2013 03:36 PM, Jakub Jelinek wrote:
What about the 4 other
maybe_constant_value on fold_non_dependent_expr_sfinae (something, tf_none)
calls in typeck.c (two for -Wdiv-by-zero and two for shift diagnostics)?
You're right, that was a poor approach to fixing the bug. This one
properly fixes potential_constant_expression to recognize that the
expression can't be constant, so it never gets to
value_dependent_expression.
commit 24c19b3d38977fafbf870ef2ea45d05f37feb36a
Author: Jason Merrill <ja...@redhat.com>
Date: Mon May 13 17:09:36 2013 -0400
PR c++/56998
* semantics.c (potential_constant_expression_1): Make sure the
called function is potentially constant.
* call.c (null_ptr_cst_p): Revert earlier change.
diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index 9f3a50d..bd8f531 100644
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -554,7 +554,7 @@ null_ptr_cst_p (tree t)
if (CP_INTEGRAL_TYPE_P (TREE_TYPE (t)))
{
/* Core issue 903 says only literal 0 is a null pointer constant. */
- if (cxx_dialect < cxx0x && !TREE_SIDE_EFFECTS (t))
+ if (cxx_dialect < cxx0x)
t = maybe_constant_value (fold_non_dependent_expr_sfinae (t, tf_none));
STRIP_NOPS (t);
if (integer_zerop (t) && !TREE_OVERFLOW (t))
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 3e78887..92a4917 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -8476,7 +8476,11 @@ potential_constant_expression_1 (tree t, bool want_rval, tsubst_flags_t flags)
}
}
else
- fun = get_first_fn (fun);
+ {
+ if (!potential_constant_expression_1 (fun, true, flags))
+ return false;
+ fun = get_first_fn (fun);
+ }
/* Skip initial arguments to base constructors. */
if (DECL_BASE_CONSTRUCTOR_P (fun))
i = num_artificial_parms_for (fun);
