From 79bef7aea4419b75e2cca0f121c6e1a4232bb03c Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Fri, 3 May 2013 23:44:54 +0000
Subject: [PATCH] <rdar://problem/13806270> A template argument list is a
 constant-evaluated context.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@181076 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Parse/ParseTemplate.cpp            | 3 +++
 test/SemaTemplate/temp_arg_nontype.cpp | 9 +++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/Parse/ParseTemplate.cpp b/lib/Parse/ParseTemplate.cpp
index fd49e7a36d..84b7df7295 100644
--- a/lib/Parse/ParseTemplate.cpp
+++ b/lib/Parse/ParseTemplate.cpp
@@ -1149,6 +1149,9 @@ bool Parser::IsTemplateArgumentList(unsigned Skip) {
 ///         template-argument-list ',' template-argument
 bool
 Parser::ParseTemplateArgumentList(TemplateArgList &TemplateArgs) {
+  // Template argument lists are constant-evaluation contexts.
+  EnterExpressionEvaluationContext EvalContext(Actions,Sema::ConstantEvaluated);
+
   while (true) {
     ParsedTemplateArgument Arg = ParseTemplateArgument();
     if (Tok.is(tok::ellipsis)) {
diff --git a/test/SemaTemplate/temp_arg_nontype.cpp b/test/SemaTemplate/temp_arg_nontype.cpp
index 210b5e463f..24509524b2 100644
--- a/test/SemaTemplate/temp_arg_nontype.cpp
+++ b/test/SemaTemplate/temp_arg_nontype.cpp
@@ -337,3 +337,12 @@ namespace rdar13000548 {
   }
 
 }
+
+namespace rdar13806270 {
+  template <unsigned N> class X { };
+  const unsigned value = 32;
+  struct Y {
+    X<value + 1> x;
+  };
+  void foo() {}
+}
-- 
2.50.1