Change Parser::ParseCaseStatement to use an iterative approach to parsing
multiple sequential case statements instead of doing it with recursion.  This
fixes a problem where we run out of stack space parsing 100K directly nested
cases.

There are a couple other problems that prevent this from being useful in 
practice (right now the example only parses correctly with -disable-free and
doesn't work with -emit-llvm), but this is a start.

I'm not including a testcase because it is large and uninteresting for 
regtesting.

Sebastian, I would appreciate it if you could scrutinize the smart pointer 
gymnastics I do.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@66011 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/Sema.h b/lib/Sema/Sema.h
index deff504..14b7287 100644
--- a/lib/Sema/Sema.h
+++ b/lib/Sema/Sema.h
@@ -995,7 +995,9 @@
                                          SourceLocation EndLoc);
   virtual OwningStmtResult ActOnCaseStmt(SourceLocation CaseLoc, ExprArg LHSVal,
                                     SourceLocation DotDotDotLoc, ExprArg RHSVal,
-                                    SourceLocation ColonLoc, StmtArg SubStmt);
+                                    SourceLocation ColonLoc);
+  virtual void ActOnCaseStmtBody(StmtTy *CaseStmt, StmtArg SubStmt);
+  
   virtual OwningStmtResult ActOnDefaultStmt(SourceLocation DefaultLoc,
                                             SourceLocation ColonLoc,
                                             StmtArg SubStmt, Scope *CurScope);