name-lookup.c (finish_using_directive): Don't issue inform() if the warning didn't trigger.

	* name-lookup.c (finish_using_directive): Don't issue inform() if the
	warning didn't trigger.  Add quoting.  Tweak the inform message.

	* g++.dg/lookup/strong-using2.C: New test.

From-SVN: r271432

gcc/cp/ChangeLog

@@ -3,6 +3,9 @@
 	* pt.c (convert_template_argument): Add a diagnostic for the
 	[temp.arg]/2 ambiguity case.
 
+	* name-lookup.c (finish_using_directive): Don't issue inform() if the
+	warning didn't trigger.  Add quoting.  Tweak the inform message.
+
 2019-05-20  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	* cp-tree.h: Remove remnants of CONV_NONCONVERTING.

gcc/cp/name-lookup.c

@@ -7258,10 +7258,10 @@ finish_using_directive (tree target, tree attribs)
 	if (current_binding_level->kind == sk_namespace
 	    && is_attribute_p ("strong", name))
 	  {
-	    warning (0, "strong using directive no longer supported");
-	    if (CP_DECL_CONTEXT (target) == current_namespace)
+	    if (warning (0, "%<strong%> using directive no longer supported")
+		&& CP_DECL_CONTEXT (target) == current_namespace)
 	      inform (DECL_SOURCE_LOCATION (target),
-		      "you may use an inline namespace instead");
+		      "you can use an inline namespace instead");
 	  }
 	else
 	  warning (OPT_Wattributes, "%qD attribute directive ignored", name);

gcc/testsuite/ChangeLog

@@ -4,6 +4,8 @@
 
 	* g++.dg/cpp2a/nontype-class17.C: New test.
 
+	* g++.dg/lookup/strong-using2.C: New test.
+
 2019-05-20  Jeff Law  <law@redhat.com>
 
 	* gcc.dg/Wtype-limits-Wextra.c: Adjust expected output after

gcc/testsuite/g++.dg/lookup/strong-using2.C

+// { dg-do compile { target c++11 } }
+// { dg-options "-w" }
+
+namespace A
+{
+  namespace B // { dg-bogus "inline namespace" }
+  {
+  }
+
+  using namespace B __attribute__ ((strong)); // { dg-bogus "no longer supported" }
+}