PR c++/50308 - wrong deprecated warning with ADL

	PR c++/17729 - duplicate deprecated warning
	* semantics.c (finish_id_expression): Only call mark_used on a
	function if we aren't building a call.

From-SVN: r245643

gcc/cp/ChangeLog

 2017-02-21  Jason Merrill  <jason@redhat.com>
 
+	PR c++/50308 - wrong deprecated warning with ADL
+	PR c++/17729 - duplicate deprecated warning
+	* semantics.c (finish_id_expression): Only call mark_used on a
+	function if we aren't building a call.
+
 	PR c++/41727 - ICE with partial spec of partial instantiation
 	* pt.c (process_partial_specialization): For now, don't check more
 	specialized if there is more than one level of args.

gcc/cp/semantics.c

@@ -3743,7 +3743,15 @@ finish_id_expression (tree id_expression,
 	  if (TREE_CODE (first_fn) == TEMPLATE_DECL)
 	    first_fn = DECL_TEMPLATE_RESULT (first_fn);
 
-	  if (!really_overloaded_fn (decl)
+	  /* [basic.def.odr]: "A function whose name appears as a
+	     potentially-evaluated expression is odr-used if it is the unique
+	     lookup result".
+
+	     But only mark it if it's a complete postfix-expression; in a call,
+	     ADL might select a different function, and we'll call mark_used in
+	     build_over_call.  */
+	  if (done
+	      && !really_overloaded_fn (decl)
 	      && !mark_used (first_fn))
 	    return error_mark_node;
 

gcc/testsuite/c-c++-common/pr69558.c

@@ -16,4 +16,4 @@
 
 __attribute__((deprecated)) void foo (void); /* { dg-bogus "declared here" "" { xfail { c++ } } } */
 
-C (foo) /* { dg-bogus "is deprecated"  "" { xfail { c++ } } } */
+C (foo) /* { dg-bogus "is deprecated" } */

gcc/testsuite/g++.dg/warn/deprecated-12.C

+// PR c++/50308
+
+void A( int ) __attribute__((deprecated));
+
+namespace B {
+
+  struct C {};
+
+  void A(C) {}
+
+}
+
+int main ()
+{
+  B::C x;
+
+  // ADL correctly identifies the non-deprecated B::A, but a warning about the
+  // global A is generated anyway
+  A( x );			// { dg-bogus "deprecated" }
+}