Fixed the forward declaration issue that was present in the DWARF parser after
adding methods to C++ and objective C classes. In order to make methods, we
need the function prototype which means we need the arguments. Parsing these
could cause a circular reference that caused an  assertion.

Added a new typedef for the clang opaque types which are just void pointers:
lldb::clang_type_t. This appears in lldb-types.h.

This was fixed by enabling struct, union, class, and enum types to only get
a forward declaration when we make the clang opaque qual type for these
types. When they need to actually be resolved, lldb_private::Type will call
a new function in the SymbolFile protocol to resolve a clang type when it is
not fully defined (clang::TagDecl::getDefinition() returns NULL). This allows
us to be a lot more lazy when parsing clang types and keeps down the amount
of data that gets parsed into the ASTContext for each module. 

Getting the clang type from a "lldb_private::Type" object now takes a boolean
that indicates if a forward declaration is ok:

    clang_type_t lldb_private::Type::GetClangType (bool forward_decl_is_ok);
    
So function prototypes that define parameters that are "const T&" can now just
parse the forward declaration for type 'T' and we avoid circular references in
the type system.



git-svn-id: https://llvm.org/svn/llvm-project/llvdb/trunk@115012 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Expression/DWARFExpression.cpp b/source/Expression/DWARFExpression.cpp
index a29994e..eef35a1 100644
--- a/source/Expression/DWARFExpression.cpp
+++ b/source/Expression/DWARFExpression.cpp
@@ -2136,7 +2136,7 @@
                     return false;
                 }
                 
-                void *array_type = array_val.GetOpaqueClangQualType();
+                void *array_type = array_val.GetClangType();
                 
                 void *member_type;
                 uint64_t size = 0;
@@ -2214,7 +2214,7 @@
                 {
                 case Value::eContextTypeOpaqueClangQualType:
                     {
-                        void *clang_type = stack.back().GetOpaqueClangQualType();
+                        void *clang_type = stack.back().GetClangType();
                         
                         if (ClangASTContext::IsAggregateType (clang_type))
                         {
@@ -2434,7 +2434,7 @@
                     return false;
                 }
                     
-                void *ptr_type = tmp.GetOpaqueClangQualType();
+                void *ptr_type = tmp.GetClangType();
                 void *target_type;
             
                 if (!ClangASTContext::IsPointerType(ptr_type, &target_type))
@@ -2483,7 +2483,7 @@
                 Value *proxy = expr_local_variable->CreateProxy();
                 stack.push_back(*proxy);
                 delete proxy;
-                //stack.back().SetContext (Value::eContextTypeOpaqueClangQualType, expr_local_variable->GetOpaqueClangQualType());
+                //stack.back().SetContext (Value::eContextTypeOpaqueClangQualType, expr_local_variable->GetClangType());
                 */
             }
             break;