On Wed, Mar 21, 2018 at 12:01:58PM -0400, Jason Merrill wrote:
> On Wed, Mar 21, 2018 at 4:42 AM, Jakub Jelinek <ja...@redhat.com> wrote:
> > On Tue, Mar 20, 2018 at 05:00:34PM -0400, Jason Merrill wrote:
> >> On Mon, Mar 19, 2018 at 3:50 PM, Jakub Jelinek <ja...@redhat.com> wrote:
> >> > +int a(__attribute__((b((int)__builtin_inf() * 1ULL / auto))));
> >>
> >> This seems like another situation like 84610 and 84642 that Alex sent
> >> a patch for, of 'auto' in an attribute wrongly being treated as an
> >> implicit template parameter. As I suggested in response to his patch,
> >> we ought to disable auto_is_implicit_function_parm_p within an
> >> attribute-specifier.
> >
> > Ok, for this specific testcase I'll wait for Alex. That doesn't mean
> > the FIX_TRUNC_EXPR handling isn't completely wrong though.
> > So, shall we fix it anyway, or remove or just gcc_unreachable ()?
> > It was added in PR51150 (it couldn't work even at that point,
> > cp_build_unary_op would use wrong return type even back then), but the
> > testcase never invokes this anymore, uses CAST_EXPR, STATIC_CAST_EXPR etc.
> > instead.
>
> Hmm, I think remove. It should then hit the gcc_unreachable() in tsubst_copy.
To my surprise, with latest Alex' changes tsubst_copy_and_build is still
called with FIX_TRUNC_EXPR (the (int) __builtin_inf () expression), but with
the following patch we don't ICE, because args is NULL and
tsubst_copy starts with:
14945 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
14946 return t;
So, do you still want the FIX_TRUNC_EXPR handling removed or fixed (as done
in the first patch)?
2018-03-22 Jakub Jelinek <ja...@redhat.com>
PR c++/84942
* pt.c (tsubst_copy_and_build): Remove FIX_TRUNC_EXPR handling.
* g++.dg/cpp1y/pr84942.C: New test.
--- gcc/cp/pt.c.jj 2018-03-20 13:53:32.265938570 +0100
+++ gcc/cp/pt.c 2018-03-21 17:25:36.155977417 +0100
@@ -17513,10 +17513,6 @@ tsubst_copy_and_build (tree t,
RECUR (TREE_OPERAND (t, 0)),
complain|decltype_flag));
- case FIX_TRUNC_EXPR:
- RETURN (cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
- false, complain));
-
case ADDR_EXPR:
op1 = TREE_OPERAND (t, 0);
if (TREE_CODE (op1) == LABEL_DECL)
--- gcc/testsuite/g++.dg/cpp1y/pr84942.C.jj 2018-03-19 11:04:16.201588211
+0100
+++ gcc/testsuite/g++.dg/cpp1y/pr84942.C 2018-03-19 11:02:37.950609950
+0100
@@ -0,0 +1,7 @@
+// PR c++/84942
+// { dg-do compile { target c++14 } }
+// { dg-options "-w" }
+
+int a(__attribute__((b((int)__builtin_inf() * 1ULL / auto))));
+// { dg-error "expected primary-expression before" "" { target *-*-* } .-1 }
+// { dg-error "declared as implicit template" "" { target *-*-* } .-2 }
Jakub
