Merge pull request #1997 from gpakosz:GTEST_IS_THREADSAFE

PiperOrigin-RevId: 224054240

README.md

@@ -16,7 +16,7 @@ This repository is a merger of the formerly separate GoogleTest and
 GoogleMock projects. These were so closely related that it makes sense to
 maintain and release them together.
 
-Please subscribe to the mailing list at googletestframework@googlegroups.com for questions, discussions, and development.  
+Please the mailing list at googletestframework@googlegroups.com for questions, discussions, and development.  
 There is also an IRC channel on [OFTC](https://webchat.oftc.net/) (irc.oftc.net) #gtest available.  
 
 Getting started information for **Google Test** is available in the

googletest/include/gtest/internal/gtest-port.h

@@ -785,13 +785,17 @@ typedef struct _RTL_CRITICAL_SECTION GTEST_CRITICAL_SECTION;
 #  define GTEST_HAS_SEH 0
 # endif
 
-#define GTEST_IS_THREADSAFE \
-    (GTEST_HAS_MUTEX_AND_THREAD_LOCAL_ \
-     || (GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT) \
-     || GTEST_HAS_PTHREAD)
-
 #endif  // GTEST_HAS_SEH
 
+#ifndef GTEST_IS_THREADSAFE
+
+#define GTEST_IS_THREADSAFE                                                 \
+  (GTEST_HAS_MUTEX_AND_THREAD_LOCAL_ ||                                     \
+   (GTEST_OS_WINDOWS && !GTEST_OS_WINDOWS_PHONE && !GTEST_OS_WINDOWS_RT) || \
+   GTEST_HAS_PTHREAD)
+
+#endif  // GTEST_IS_THREADSAFE
+
 // GTEST_API_ qualifies all symbols that must be exported. The definitions below
 // are guarded by #ifndef to give embedders a chance to define GTEST_API_ in
 // gtest/internal/custom/gtest-port.h