diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index c2ae32f0132..7a334ff8464 100644
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -29,6 +29,7 @@
 #include "llvm/Target/TargetData.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <algorithm>
 using namespace llvm;
@@ -207,6 +208,8 @@ static const Function *getParent(const Value *V) {
   return NULL;
 }
 
+static bool sameParent(const Value *O1, const Value *O2) ATTRIBUTE_UNUSED;
+
 static bool sameParent(const Value *O1, const Value *O2) {
 
   const Function *F1 = getParent(O1);