Switch assert(0/false) llvm_unreachable.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@140367 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index f1c6d12..7380401 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -1585,7 +1585,7 @@
   // TODO: Build AST.
 
   switch (T) {
-  default: assert(0 && "Not a builtin primary expression!");
+  default: llvm_unreachable("Not a builtin primary expression!");
   case tok::kw___builtin_va_arg: {
     ExprResult Expr(ParseAssignmentExpression());