Accept over-qualified constructor in MSVC emulation mode

MSVC accepts this:

class A {
  A::A();
};

Clang accepts regular member functions with extra qualification as an MS
extension, but not constructors.  This changes the parser to defer rejecting
qualified constructors so that the same Sema logic can apply to constructors as
regular member functions.  This also improves the error message when MS
extensions are disabled (in my opinion). Before it was:

/Users/jason/Desktop/test.cpp:2:8: error: expected member name or ';' after declaration specifiers
  A::A();
  ~~~~ ^
1 error generated.

After:

/Users/jason/Desktop/test.cpp:2:6: error: extra qualification on member 'A'
  A::A();
  ~~~^
1 error generated.

Patch by Jason Haslam.

llvm-svn: 174980

clang/lib/Parse/ParseDecl.cpp

@@ -2274,8 +2274,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
         // name, then the code is ill-formed; this interpretation is
         // reinforced by the NAD status of core issue 635.
         TemplateIdAnnotation *TemplateId = takeTemplateIdAnnotation(Next);
-        if ((DSContext == DSC_top_level ||
-             (DSContext == DSC_class && DS.isFriendSpecified())) &&
+        if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
             TemplateId->Name &&
             Actions.isCurrentClassName(*TemplateId->Name, getCurScope(), &SS)) {
           if (isConstructorDeclarator()) {
@@ -2325,8 +2324,7 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
 
       // If we're in a context where the identifier could be a class name,
       // check whether this is a constructor declaration.
-      if ((DSContext == DSC_top_level ||
-           (DSContext == DSC_class && DS.isFriendSpecified())) &&
+      if ((DSContext == DSC_top_level || DSContext == DSC_class) &&
           Actions.isCurrentClassName(*Next.getIdentifierInfo(), getCurScope(),
                                      &SS)) {
         if (isConstructorDeclarator())
@@ -4445,8 +4443,7 @@ void Parser::ParseDirectDeclarator(Declarator &D) {
       else if (D.getCXXScopeSpec().isSet())
         AllowConstructorName =
           (D.getContext() == Declarator::FileContext ||
-           (D.getContext() == Declarator::MemberContext &&
-            D.getDeclSpec().isFriendSpecified()));
+           D.getContext() == Declarator::MemberContext);
       else
         AllowConstructorName = (D.getContext() == Declarator::MemberContext);
 

clang/test/CXX/special/class.ctor/p1.cpp

@@ -1,5 +1,5 @@
 // RUN: %clang_cc1 -fsyntax-only -verify %s
-// expected-no-diagnostics
+
 struct X0 {
   struct type { };
 
@@ -41,3 +41,7 @@ template<typename T> X1<T>::X1() { }
 template<typename T> (X1<T>::X1)(double) { }
 template<typename T> X1<T> X1<T>::f1(int) { return 0; }
 template<typename T> X1<T> (X1<T>::f1)(type) { return 0; }
+
+class A {
+  A::A(); // expected-error{{extra qualification on member 'A'}}
+};

clang/test/SemaCXX/MicrosoftExtensions.cpp

@@ -204,3 +204,7 @@ struct PR11150 {
 void f() { int __except = 0; }
 
 void ::f(); // expected-warning{{extra qualification on member 'f'}}
+
+class C {
+  C::C(); // expected-warning{{extra qualification on member 'C'}}
+};