From 906ed278b96692cdb9546c16ea1f958b6213d9e1 Mon Sep 17 00:00:00 2001
From: David Majnemer <david.majnemer@gmail.com>
Date: Tue, 13 Jan 2015 05:28:24 +0000
Subject: [PATCH] Parse: Don't crash if missing an initializer expression

llvm-svn: 225768
---
 clang/lib/Parse/ParseDecl.cpp          | 3 ++-
 clang/test/Parser/cxx-default-args.cpp | 4 ++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 0d8b0cc..93125e9 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -5625,13 +5625,14 @@ void Parser::ParseParameterDeclarationClause(
           // FIXME: Can we use a smart pointer for Toks?
           DefArgToks = new CachedTokens;
 
+          SourceLocation ArgStartLoc = NextToken().getLocation();
           if (!ConsumeAndStoreInitializer(*DefArgToks, CIK_DefaultArgument)) {
             delete DefArgToks;
             DefArgToks = nullptr;
             Actions.ActOnParamDefaultArgumentError(Param, EqualLoc);
           } else {
             Actions.ActOnParamUnparsedDefaultArgument(Param, EqualLoc,
-                                                (*DefArgToks)[1].getLocation());
+                                                      ArgStartLoc);
           }
         } else {
           // Consume the '='.
diff --git a/clang/test/Parser/cxx-default-args.cpp b/clang/test/Parser/cxx-default-args.cpp
index f0e2e69..0c028f7 100644
--- a/clang/test/Parser/cxx-default-args.cpp
+++ b/clang/test/Parser/cxx-default-args.cpp
@@ -36,3 +36,7 @@ struct T {
 struct S { 
   void f(int &r = error);  // expected-error {{use of undeclared identifier 'error'}}
 };
+
+struct U {
+  void i(int x = ) {} // expected-error{{expected expression}}
+};
-- 
2.7.4