diff --git a/googletest/include/gtest/internal/gtest-param-util.h b/googletest/include/gtest/internal/gtest-param-util.h
index 41a16bfb..0d4aafc5 100644
--- a/googletest/include/gtest/internal/gtest-param-util.h
+++ b/googletest/include/gtest/internal/gtest-param-util.h
@@ -652,9 +652,9 @@ class ParameterizedTestSuiteInfo : public ParameterizedTestSuiteInfoBase {
   };
   typedef ::std::vector<InstantiationInfo> InstantiationContainer;
   
-  static std::string validParamChars = "_-:/";
-
   static bool IsValidParamName(const std::string& name) {
+    static constexpr validParamChars = "_-:/";
+
     // Check for empty string
     if (name.empty()) return false;