Improve support for out-of-line definitions of nested templates and
their members, including member class template, member function
templates, and member classes and functions of member templates.

To actually parse the nested-name-specifiers that qualify the name of
an out-of-line definition of a member template, e.g.,

  template<typename X> template<typename Y>
  X Outer<X>::Inner1<Y>::foo(Y) {
    return X();
  }

we need to look for the template names (e.g., "Inner1") as a member of
the current instantiation (Outer<X>), even before we have entered the
scope of the current instantiation. Since we can't do this in general
(i.e., we should not be looking into all dependent
nested-name-specifiers as if they were the current instantiation), we
rely on the parser to tell us when it is parsing a declaration
specifier sequence, and, therefore, when we should consider the
current scope specifier to be a current instantiation.

Printing of complicated, dependent nested-name-specifiers may be
somewhat broken by this commit; I'll add tests for this issue and fix
the problem (if it still exists) in a subsequent commit.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@80044 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseExprCXX.cpp b/lib/Parse/ParseExprCXX.cpp
index 46526e4..d97bc2d 100644
--- a/lib/Parse/ParseExprCXX.cpp
+++ b/lib/Parse/ParseExprCXX.cpp
@@ -30,10 +30,11 @@
 ///         nested-name-specifier identifier '::'
 ///         nested-name-specifier 'template'[opt] simple-template-id '::' [TODO]
 ///
-bool Parser::ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS) {
+bool Parser::ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS,
+                                            bool EnteringContext) {
   assert(getLang().CPlusPlus &&
          "Call sites of this function should be guarded by checking for C++");
-
+  
   if (Tok.is(tok::annot_cxxscope)) {
     SS.setScopeRep(Tok.getAnnotationValue());
     SS.setRange(Tok.getAnnotationRange());
@@ -106,7 +107,6 @@
       if (TemplateId->Kind == TNK_Type_template || 
           TemplateId->Kind == TNK_Dependent_template_name) {
         AnnotateTemplateIdTokenAsType(&SS);
-        SS.setScopeRep(0);
 
         assert(Tok.is(tok::annot_typename) && 
                "AnnotateTemplateIdTokenAsType isn't working");
@@ -164,7 +164,8 @@
         continue;
       
       SS.setScopeRep(
-        Actions.ActOnCXXNestedNameSpecifier(CurScope, SS, IdLoc, CCLoc, II));
+        Actions.ActOnCXXNestedNameSpecifier(CurScope, SS, IdLoc, CCLoc, II,
+                                            EnteringContext));
       SS.setEndLoc(CCLoc);
       continue;
     }
@@ -173,8 +174,9 @@
     //   type-name '<'
     if (Next.is(tok::less)) {
       TemplateTy Template;
-      if (TemplateNameKind TNK = Actions.isTemplateName(II, CurScope,
-                                                        Template, &SS)) {
+      if (TemplateNameKind TNK = Actions.isTemplateName(II, CurScope, &SS,
+                                                        EnteringContext,
+                                                        Template)) {
         // We have found a template name, so annotate this this token
         // with a template-id annotation. We do not permit the
         // template-id to be translated into a type annotation,