PR c++/61490 - qualified-id in friend function definition.

	* decl.c (grokdeclarator): Diagnose qualified-id in friend function
	definition.  Improve location for diagnostics of friend functions.

	* g++.dg/diagnostic/friend2.C: New test.
	* g++.dg/diagnostic/friend3.C: New test.

From-SVN: r272572

gcc/cp/ChangeLog

 2019-06-21  Marek Polacek  <polacek@redhat.com>
 
+	PR c++/61490 - qualified-id in friend function definition.
+	* decl.c (grokdeclarator): Diagnose qualified-id in friend function
+	definition.  Improve location for diagnostics of friend functions.
+
 	PR c++/60223 - ICE with T{} in non-deduced context.
 	* pt.c (unify): Allow COMPOUND_LITERAL_P in a non-deduced context.
 

gcc/cp/decl.c

@@ -11624,13 +11624,29 @@ grokdeclarator (const cp_declarator *declarator,
 		    friendp = 0;
 		  }
 		if (decl_context == NORMAL)
-		  error ("friend declaration not in class definition");
+		  error_at (declarator->id_loc,
+			    "friend declaration not in class definition");
 		if (current_function_decl && funcdef_flag)
 		  {
-		    error ("cannot define friend function %qs in a local "
-			   "class definition", name);
+		    error_at (declarator->id_loc,
+			      "cannot define friend function %qs in a local "
+			      "class definition", name);
 		    friendp = 0;
 		  }
+		/* [class.friend]/6: A function can be defined in a friend
+		   declaration if the function name is unqualified.  */
+		if (funcdef_flag && in_namespace)
+		  {
+		    if (in_namespace == global_namespace)
+		      error_at (declarator->id_loc,
+				"friend function definition %qs cannot have "
+				"a name qualified with %<::%>", name);
+		    else
+		      error_at (declarator->id_loc,
+				"friend function definition %qs cannot have "
+				"a name qualified with %<%D::%>", name,
+				in_namespace);
+		  }
 	      }
 	    else if (ctype && sfk == sfk_conversion)
 	      {

gcc/testsuite/ChangeLog

 2019-06-21  Marek Polacek  <polacek@redhat.com>
 
+	PR c++/61490 - qualified-id in friend function definition.
+	* g++.dg/diagnostic/friend2.C: New test.
+	* g++.dg/diagnostic/friend3.C: New test.
+
 	PR c++/60223 - ICE with T{} in non-deduced context.
 	* g++.dg/cpp0x/nondeduced1.C: New test.
 	* g++.dg/cpp0x/nondeduced2.C: New test.

gcc/testsuite/g++.dg/diagnostic/friend2.C

+// PR c++/61490
+// { dg-do compile }
+
+namespace N { void f (); }
+void f2 ();
+
+struct A {
+  friend void N::f () { } // { dg-error "15:friend function definition 'f' cannot have a name qualified with 'N::'" }
+  friend void ::f2 () { } // { dg-error "15:friend function definition 'f2' cannot have a name qualified with '::'" }
+};

gcc/testsuite/g++.dg/diagnostic/friend3.C

+// { dg-do compile }
+
+void
+fn ()
+{
+  struct S {
+    friend void bar () { } // { dg-error "17:cannot define friend function 'bar' in a local class definition" }
+  };
+}