Fix PR c++/69961 (invalid ctor call with dependent args)

gcc/cp/ChangeLog:

	PR c++/68948
	PR c++/69961
	* pt.c (tsubst_baselink): Reinstate the check for an invalid
	constructor call.

gcc/testsuite/ChangeLog:

	PR c++/69961
	* g++.dg/template/pr69961a.C: New test.
	* g++.dg/template/pr69961b.C: New test.

From-SVN: r233838

gcc/cp/ChangeLog

@@ -1,3 +1,10 @@
+2016-03-01  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/68948
+	PR c++/69961
+	* pt.c (tsubst_baselink): Reinstate the check for an invalid
+	constructor call.
+
 2016-02-28  Jason Merrill  <jason@redhat.com>
 
 	PR c++/69995

gcc/cp/pt.c

@@ -13622,7 +13622,15 @@ tsubst_baselink (tree baselink, tree object_type,
       name = mangle_conv_op_name_for_type (optype);
     baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
     if (!baselink)
-      return error_mark_node;
+      {
+	if (constructor_name_p (name, qualifying_scope))
+	  {
+	    if (complain & tf_error)
+	      error ("cannot call constructor %<%T::%D%> directly",
+		     qualifying_scope, name);
+	  }
+	return error_mark_node;
+      }
 
     /* If lookup found a single function, mark it as used at this
        point.  (If it lookup found multiple functions the one selected

gcc/testsuite/ChangeLog

@@ -1,3 +1,9 @@
+2016-03-01  Patrick Palka  <ppalka@gcc.gnu.org>
+
+	PR c++/69961
+	* g++.dg/template/pr69961a.C: New test.
+	* g++.dg/template/pr69961b.C: New test.
+
 2016-02-29  David Malcolm  <dmalcolm@redhat.com>
 
 	PR preprocessor/69985

gcc/testsuite/g++.dg/template/pr69961a.C

@@ -0,0 +1,25 @@
+// PR c++/69961
+// { dg-do compile { target c++11 } }
+
+#include <string>
+
+using std::string;
+
+class Format {
+ public:
+  explicit Format(string formatted) {}
+  string buffer;
+};
+
+string StrCat(const string& a) {
+  return "";
+}
+
+template <typename... AV>
+Format Message(string msg, const AV&... args) {
+  return Format::Format(StrCat(msg, args...)); // { dg-error "cannot call constructor" }
+}
+
+int main(int, char**) {
+  Message("msg");
+}

gcc/testsuite/g++.dg/template/pr69961b.C

@@ -0,0 +1,15 @@
+// PR c++/69961
+
+struct A { A (int); };
+
+template <typename T>
+void foo ()
+{
+  A::A ((T)0); // { dg-error "cannot call constructor .A::A. directly" }
+}
+
+void
+bar ()
+{
+  foo<int> ();
+}