Hi,
submitter and Manuel analyzed this a while ago and came to the
conclusion - which I think is still valid vs the current working draft -
that strictly speaking this kind of code violates [dcl.dcl], thus a
pedwarn seems more suited than a plain warning. The below one-liner,
suggested by Manuel at the time, passes testing on x86_64-linux together
with my testsuite changes.
Thanks,
Paolo.
//////////////////////
/cp
2017-06-16 Manuel Lopez-Ibanez <m...@gcc.gnu.org>
Paolo Carlini <paolo.carl...@oracle.com>
PR c++/64644
* decl2.c (finish_anon_union): Complain about "anonymous union with
no members" with a pedwarn.
/testsuite
2017-06-16 Manuel Lopez-Ibanez <m...@gcc.gnu.org>
Paolo Carlini <paolo.carl...@oracle.com>
PR c++/64644
* g++.dg/other/anon-union4.C: New.
* g++.old-deja/g++.law/union4.C: Adjust.
* g++.old-deja/g++.other/anon1.C: Likewise.
Index: cp/decl2.c
===================================================================
--- cp/decl2.c (revision 249233)
+++ cp/decl2.c (working copy)
@@ -1559,7 +1559,7 @@ finish_anon_union (tree anon_union_decl)
return;
if (main_decl == NULL_TREE)
{
- warning (0, "anonymous union with no members");
+ pedwarn (input_location, 0, "anonymous union with no members");
return;
}
Index: testsuite/g++.dg/other/anon-union4.C
===================================================================
--- testsuite/g++.dg/other/anon-union4.C (revision 0)
+++ testsuite/g++.dg/other/anon-union4.C (working copy)
@@ -0,0 +1,3 @@
+// PR c++/64644
+
+static union { }; // { dg-error "anonymous union with no members" }
Index: testsuite/g++.old-deja/g++.law/union4.C
===================================================================
--- testsuite/g++.old-deja/g++.law/union4.C (revision 249233)
+++ testsuite/g++.old-deja/g++.law/union4.C (working copy)
@@ -10,4 +10,4 @@ static union {
struct SS {
int ss;
};
-};// { dg-warning "no members" }
+};// { dg-error "no members" }
Index: testsuite/g++.old-deja/g++.other/anon1.C
===================================================================
--- testsuite/g++.old-deja/g++.other/anon1.C (revision 249233)
+++ testsuite/g++.old-deja/g++.other/anon1.C (working copy)
@@ -3,4 +3,4 @@
static union {
union {
};
-}; // { dg-warning "" } anonymous union with no members
+}; // { dg-error "" } anonymous union with no members
