PR c++/88757 - qualified name treated wrongly as type.

* parser.c (cp_parser_direct_declarator): don't treat qualified-ids
	in parameter-list as types if name lookup for declarator-id didn't
	find one or more function templates.

	* g++.dg/cpp0x/dependent2.c: new test.
	* g++.dg/cpp2a/typename10.c: remove dg-error.
	* g++.dg/cpp2a/typename12.c: new test.
	* g++.dg/template/static30.c: remove dg-error.

From-SVN: r268192

gcc/cp/ChangeLog

@@ -1,3 +1,10 @@
+2019-01-23  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/88757 - qualified name treated wrongly as type.
+	* parser.c (cp_parser_direct_declarator): Don't treat qualified-ids
+	in parameter-list as types if name lookup for declarator-id didn't
+	find one or more function templates.
+
 2019-01-23  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/44715

gcc/cp/parser.c

@@ -21098,6 +21098,33 @@ cp_parser_direct_declarator (cp_parser* parser,
 
 	    if (pack_expansion_p)
 	      maybe_warn_variadic_templates ();
+
+	    /* We're looking for this case in [temp.res]:
+	       A qualified-id is assumed to name a type if [...]
+	       - it is a decl-specifier of the decl-specifier-seq of a
+		 parameter-declaration in a declarator of a function or
+		 function template declaration, ... */
+	    if (cxx_dialect >= cxx2a
+		&& (flags & CP_PARSER_FLAGS_TYPENAME_OPTIONAL)
+		&& declarator->kind == cdk_id
+		/* ...whose declarator-id is qualified.  */
+		&& qualifying_scope != NULL_TREE
+		&& !at_class_scope_p ()
+		&& cp_lexer_next_token_is (parser->lexer, CPP_OPEN_PAREN))
+	      {
+		/* Now we have something like
+		   template <typename T> int C::x(S::p);
+		   which can be a function template declaration or a
+		   variable template definition.  If name lookup for
+		   the declarator-id C::x finds one or more function
+		   templates, assume S::p to name a type.  Otherwise,
+		   don't.  */
+		tree decl
+		  = cp_parser_lookup_name_simple (parser, unqualified_name,
+						  token->location);
+		if (!is_overloaded_fn (decl))
+		  flags &= ~CP_PARSER_FLAGS_TYPENAME_OPTIONAL;
+	      }
 	  }
 
 	handle_declarator:;

gcc/testsuite/ChangeLog

@@ -1,3 +1,11 @@
+2019-01-23  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/88757 - qualified name treated wrongly as type.
+	* g++.dg/cpp0x/dependent2.C: New test.
+	* g++.dg/cpp2a/typename10.C: Remove dg-error.
+	* g++.dg/cpp2a/typename12.C: New test.
+	* g++.dg/template/static30.C: Remove dg-error.
+
 2019-01-23  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c/44715

gcc/testsuite/g++.dg/cpp0x/dependent2.C

@@ -0,0 +1,10 @@
+// PR c++/88757
+// { dg-do compile { target c++11 } }
+
+template <class T> struct C {
+    static int x;
+};
+template <class U> struct S {
+    static const int size = 1;
+};
+template <class T> int C<T>::x(S<T>::size);

gcc/testsuite/g++.dg/cpp2a/typename10.C

@@ -11,7 +11,7 @@ namespace N2 {
   template<typename T> extern T::type v; // #1a
   //template<typename T> T::type v(typename T::value); // #1b
 }
-template<typename T> T::type N2::v(T::value); // { dg-error "" }
+template<typename T> T::type N2::v(T::value);
 
 namespace A {
   inline namespace B { template<typename T> int f(typename T::foo); }

gcc/testsuite/g++.dg/cpp2a/typename12.C

@@ -0,0 +1,20 @@
+// P0634R3
+// { dg-do compile { target c++2a } }
+
+struct W {
+  template<typename T>
+  static int fn1 (T::X);
+  template<typename T>
+  static int fn2 (T::X);
+  template<typename T>
+  static int fn2 (T::X, int);
+};
+
+template<typename T>
+int W::fn1 (T::X p) { return p; }
+
+template<typename T>
+int W::fn2 (T::X p) { return p; }
+
+template<typename T>
+int fn2 (typename T::X p) { return p; }

gcc/testsuite/g++.dg/template/static30.C

@@ -6,5 +6,5 @@ template <int> struct A
   static const int i2;
 };
 
-template <int N> const int A<N>::i1(A<N>::i); // { dg-error "no declaration matches" "" { target c++2a } }
+template <int N> const int A<N>::i1(A<N>::i);
 template <int N> const int A<N>::i2(3, A<N>::i); // { dg-error "expression list" }