diff --git a/unittests/ADT/FoldingSet.cpp b/unittests/ADT/FoldingSet.cpp
new file mode 100644
index 00000000000..a18a0df9571
--- /dev/null
+++ b/unittests/ADT/FoldingSet.cpp
@@ -0,0 +1,39 @@
+//===- llvm/unittest/ADT/FoldingSetTest.cpp -------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// FoldingSet unit tests.
+//
+//===----------------------------------------------------------------------===//
+
+#include "gtest/gtest.h"
+#include "llvm/ADT/FoldingSet.h"
+#include <string>
+
+using namespace llvm;
+
+namespace {
+
+// Unaligned string test.
+TEST(FoldingSetTest, UnalignedStringTest) {
+  SCOPED_TRACE("UnalignedStringTest");
+
+  FoldingSetNodeID a, b;
+  // An aligned string
+  std::string str1= "a test string";
+  a.AddString(str1);
+
+  // An unaligned string
+  std::string str2 = ">" + str1;
+  b.AddString(str2.c_str() + 1);
+
+  EXPECT_EQ(a.ComputeHash(), b.ComputeHash());
+}
+
+}
+
diff --git a/unittests/CMakeLists.txt b/unittests/CMakeLists.txt
index eaecc9cc0ba..76b76f2b88f 100644
--- a/unittests/CMakeLists.txt
+++ b/unittests/CMakeLists.txt
@@ -43,6 +43,7 @@ add_llvm_unittest(ADT
   ADT/DeltaAlgorithmTest.cpp
   ADT/DenseMapTest.cpp
   ADT/DenseSetTest.cpp
+  ADT/FoldingSet.cpp
   ADT/ilistTest.cpp
   ADT/ImmutableSetTest.cpp
   ADT/IntervalMapTest.cpp