re PR c++/64644 ("warning: anonymous union with no members" should be an error…

re PR c++/64644 ("warning: anonymous union with no members" should be an error with -pedantic-errors)

/cp
2017-09-15  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
	    Paolo Carlini  <paolo.carlini@oracle.com>

	PR c++/64644
	* decl2.c (finish_anon_union): Complain about "anonymous union with
	no members" with a pedwarn.

/testsuite
2017-09-15  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
	    Paolo Carlini  <paolo.carlini@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.

Co-Authored-By: Paolo Carlini <paolo.carlini@oracle.com>

From-SVN: r252835

gcc/cp/ChangeLog

+2017-09-15  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+	    Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/64644
+	* decl2.c (finish_anon_union): Complain about "anonymous union with
+	no members" with a pedwarn.
+
 2017-09-15  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* typeck.c (build_reinterpret_cast_1,

gcc/cp/decl2.c

@@ -1546,7 +1546,7 @@ 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;
     }
 

gcc/testsuite/ChangeLog

+2017-09-15  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>
+	    Paolo Carlini  <paolo.carlini@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.
+
 2017-09-15  Bernd Edlinger  <bernd.edlinger@hotmail.de>
 
 	* c-c++-common/Wcast-align.c: New test.

gcc/testsuite/g++.dg/other/anon-union4.C

+// PR c++/64644
+
+static union { };  // { dg-error "anonymous union with no members" }

gcc/testsuite/g++.old-deja/g++.law/union4.C

@@ -10,4 +10,4 @@ static union {
         struct SS {
                 int ss;
         };
-};// { dg-warning "no members" }
+};// { dg-error "no members" }

gcc/testsuite/g++.old-deja/g++.other/anon1.C

@@ -3,4 +3,4 @@
 static union {
   union {
   };
-}; // { dg-warning "" } anonymous union with no members
+}; // { dg-error "" } anonymous union with no members