re PR c++/69855 (Missing diagnostic for overload that only differs by return type)

/cp
	PR c++/69855
	* name-lookup.c (pushdecl_maybe_friend_1): Push local function
	decls into the global scope after stripping template bits
	and setting DECL_ANTICIPATED.

/testsuite
	PR c++/69855
	* g++.dg/overload/69855.C: New.
	* g++.old-deja/g++.law/missed-error2.C: Adjust.
	* g++.old-deja/g++.pt/crash3.C: Likewise.

From-SVN: r236826

gcc/cp/ChangeLog

+2016-05-27  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	PR c++/69855
+	* name-lookup.c (pushdecl_maybe_friend_1): Push local function
+	decls into the global scope after stripping template bits
+	and setting DECL_ANTICIPATED.
+
 2016-05-26  Jakub Jelinek  <jakub@redhat.com>
 
 	* semantics.c (finish_omp_clauses) <case OMP_CLAUSE_SCHEDULE>: Warn

gcc/cp/name-lookup.c

@@ -929,6 +929,24 @@ pushdecl_maybe_friend_1 (tree x, bool is_friend)
 	      DECL_ANTICIPATED (t) = 1;
 	      DECL_HIDDEN_FRIEND_P (t) = 1;
 	    }
+
+	  if (TREE_CODE (x) == FUNCTION_DECL
+	      && DECL_LOCAL_FUNCTION_P (x)
+	      && !DECL_OMP_DECLARE_REDUCTION_P (x)
+	      && !type_dependent_expression_p (x))
+	    {
+	      /* PR c++/69855, a local function declaration
+		 is stripped from template info and pushed to
+		 the local scope as a hidden declaration. This
+		 allows ill-formed overloads even in other scopes
+		 to be diagnosed both at the local declaration site
+		 and after it.  */
+	      tree t2 = copy_decl (t);
+	      DECL_USE_TEMPLATE (t2) = 0;
+	      DECL_TEMPLATE_INFO (t2) = NULL_TREE;
+	      DECL_ANTICIPATED (t2) = 1;
+	      push_overloaded_decl (t2, PUSH_GLOBAL, is_friend);
+	    }
 	}
 
       if (t != x || DECL_FUNCTION_TEMPLATE_P (t))

gcc/testsuite/ChangeLog

+2016-05-27  Ville Voutilainen  <ville.voutilainen@gmail.com>
+
+	PR c++/69855
+	* g++.dg/overload/69855.C: New.
+	* g++.old-deja/g++.law/missed-error2.C: Adjust.
+	* g++.old-deja/g++.pt/crash3.C: Likewise.
+
 2016-05-27  Jiong Wang  <jiong.wang@arm.com>
 
 	PR target/63596

gcc/testsuite/g++.dg/overload/69855.C

+// PR c++/69855
+// { dg-do compile }
+
+int get();
+void f() {
+  char get(); // { dg-error "ambiguating" }
+}
+
+int get2();
+char get2(int);
+void f2() {
+  char get2(); // { dg-error "ambiguating" }
+}
+
+char get3(int);
+void f3() {
+  char get3();
+}
+
+void f4() {
+  char get4();
+}
+int get4(); // { dg-error "ambiguating" }
+
+void get5();
+
+template <class T> struct X
+{
+  void g()
+  {
+    int get5(); // { dg-error "ambiguating" }
+  }
+};
+
+
+template <class T> struct X2
+{
+  void g()
+  {
+    int get6();
+  }
+};
+
+void get6(); // { dg-error "ambiguating" }

gcc/testsuite/g++.old-deja/g++.law/missed-error2.C

@@ -25,9 +25,10 @@ int main() {
    foo(4, -37, 14.39, 14.38);
 }
 
-// 971006 we no longer give an error for this since we emit a hard error
-// about the declaration above
-static void foo(int i, int j, double x, double y) { 
+// 971006 we no longer gave an error for this since we emit a hard error
+// about the declaration above, but after the fix for PR c++/69855
+// this declaration emits a diagnostic again
+static void foo(int i, int j, double x, double y) { // { dg-error "extern|static" }
 
    std::cout << "Max(int): " << max(i,j) << " Max(double): " <<
 max(x,y) << '\n';

gcc/testsuite/g++.old-deja/g++.pt/crash3.C

@@ -10,7 +10,7 @@ public:
     }
     CVector<long> g() const
     {
-       CVector<long> v();
-       return v;
+       CVector<long> v2();
+       return v2;
     }
 };