diff --git a/googletest/include/gtest/internal/gtest-port.h b/googletest/include/gtest/internal/gtest-port.h
index 0003d276..c9e1f324 100644
--- a/googletest/include/gtest/internal/gtest-port.h
+++ b/googletest/include/gtest/internal/gtest-port.h
@@ -1710,7 +1710,7 @@ typedef GTestMutexLock MutexLock;
 // C-linkage.  Therefore it cannot be templatized to access
 // ThreadLocal<T>.  Hence the need for class
 // ThreadLocalValueHolderBase.
-class ThreadLocalValueHolderBase {
+class GTEST_API_ ThreadLocalValueHolderBase {
  public:
   virtual ~ThreadLocalValueHolderBase() {}
 };