Introduce a new representation for template template

parameters. Rather than storing them as either declarations (for the
non-dependent case) or expressions (for the dependent case), we now
(always) store them as TemplateNames. 

The primary change here is to add a new kind of TemplateArgument,
which stores a TemplateName. However, making that change ripples to
every switch on a TemplateArgument's kind, also affecting
TemplateArgumentLocInfo/TemplateArgumentLoc, default template
arguments for template template parameters, type-checking of template
template arguments, etc.

This change is light on testing. It should fix several pre-existing
problems with template template parameters, such as:
  - the inability to use dependent template names as template template
  arguments
  - template template parameter default arguments cannot be
  instantiation

However, there are enough pieces missing that more implementation is
required before we can adequately test template template parameters. 



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@86777 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 3 insertions, 0 deletions

diff --git a/lib/AST/Type.cpp b/lib/AST/Type.cpp
index 844589fd3e..5ecc33cd8f 100644
--- a/lib/AST/Type.cpp
+++ b/lib/AST/Type.cpp
@@ -807,6 +807,9 @@ static bool isDependent(const TemplateArgument &Arg) {
   case TemplateArgument::Type:
     return Arg.getAsType()->isDependentType();
 
+  case TemplateArgument::Template:
+    return Arg.getAsTemplate().isDependent();
+      
   case TemplateArgument::Declaration:
   case TemplateArgument::Integral:
     // Never dependent