re PR c++/79290 (forming pointer to member function tries to access "__pfn")

	PR c++/79290
	* typeck.c (build_ptrmemfunc_access_expr): Set TREE_NO_WARNING.

	PR c++/79290
	* g++.dg/warn/pr79290.C: New.

From-SVN: r245069

gcc/cp/ChangeLog

 2017-01-31  Nathan Sidwell  <nathan@acm.org>
 
+	PR c++/79290
+	* typeck.c (build_ptrmemfunc_access_expr): Set TREE_NO_WARNING.
+
 	PR c++/67273
 	PR c++/79253
 	* pt.c: (instantiate_decl): Push to top level when current

gcc/cp/typeck.c

@@ -2950,7 +2950,10 @@ build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
        member = DECL_CHAIN (member))
     if (DECL_NAME (member) == member_name)
       break;
-  return build_simple_component_ref (ptrmem, member);
+  tree res = build_simple_component_ref (ptrmem, member);
+
+  TREE_NO_WARNING (res) = 1;
+  return res;
 }
 
 /* Given an expression PTR for a pointer, return an expression

gcc/testsuite/ChangeLog

 2017-01-31  Nathan Sidwell  <nathan@acm.org>
 
+	PR c++/79290
+	* g++.dg/warn/pr79290.C: New.
+
 	PR c++/67273
 	PR c++/79253
 	* g++.dg/cpp1y/pr67273.C: New.

gcc/testsuite/g++.dg/warn/pr79290.C

+// { dg-additional-options "-Wall" }
+// PR 79290, bogus warning looking inside PMF
+
+struct Song {
+  int get() const ;
+};
+
+typedef int (Song::*PMF_t)() const;
+
+struct SongTag {
+  PMF_t function () const;
+};
+
+
+template<typename T>
+struct Printer {
+  bool Foo(const SongTag &st) {
+    return st.function () == &Song::get;
+  }
+};
+
+void Baz (Printer<int> *p, SongTag const &st)
+{
+  p->Foo (st);
+}