Fix the isReferenced bit on parameters in a couple of edge cases.  PR12153.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151837 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 027ec73..1492011 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -9630,6 +9630,7 @@
   //   An entity captured by a lambda-expression is odr-used (3.2) in
   //   the scope containing the lambda-expression.
   Expr *Ref = new (S.Context) DeclRefExpr(Var, DeclRefType, VK_LValue, Loc);
+  Var->setReferenced(true);
   Var->setUsed(true);
 
   // When the field has array type, create index variables for each
diff --git a/lib/Sema/SemaTemplateVariadic.cpp b/lib/Sema/SemaTemplateVariadic.cpp
index 15a3085..3a547dd 100644
--- a/lib/Sema/SemaTemplateVariadic.cpp
+++ b/lib/Sema/SemaTemplateVariadic.cpp
@@ -779,6 +779,8 @@
     return ExprError();
   }
 
+  MarkAnyDeclReferenced(OpLoc, ParameterPack);
+
   return new (Context) SizeOfPackExpr(Context.getSizeType(), OpLoc, 
                                       ParameterPack, NameLoc, RParenLoc);
 }
diff --git a/test/SemaCXX/warn-unused-parameters.cpp b/test/SemaCXX/warn-unused-parameters.cpp
index 75d8dcc..00ce1a9 100644
--- a/test/SemaCXX/warn-unused-parameters.cpp
+++ b/test/SemaCXX/warn-unused-parameters.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -Wunused-parameter -verify %s
+// RUN: %clang_cc1 -fsyntax-only -Wunused-parameter -verify -std=c++11 %s
 template<typename T>
 struct X {
   T f0(T x);
@@ -24,3 +24,11 @@
   x.f4(i);
   x.f5(i);
 }
+
+// Make sure both parameters aren't considered unused.
+template <typename... T>
+static int test_pack(T... t, T... s)
+{
+  auto l = [&t...]() { return sizeof...(s); };
+  return l();
+}