diff --git a/concurrentqueue.h b/concurrentqueue.h
index 4b2ad791..99caefc0 100644
--- a/concurrentqueue.h
+++ b/concurrentqueue.h
@@ -105,7 +105,7 @@ namespace moodycamel { namespace details {
 	static const thread_id_t invalid_thread_id2 = 0xFFFFFFFFU;	// Not technically guaranteed to be invalid, but is never used in practice. Note that all Win32 thread IDs are presently multiples of 4.
 	static inline thread_id_t thread_id() { return static_cast<thread_id_t>(::GetCurrentThreadId()); }
 } }
-#elif defined(__arm__) || defined(_M_ARM) || defined(__aarch64__) || (defined(__APPLE__) && TARGET_OS_IPHONE) || defined(MOODYCAMEL_NO_THREAD_LOCAL)
+#elif defined(__arm__) || defined(_M_ARM) || defined(__aarch64__) || (defined(__APPLE__) && TARGET_OS_IPHONE) || defined(__MVS__) || defined(MOODYCAMEL_NO_THREAD_LOCAL)
 namespace moodycamel { namespace details {
 	static_assert(sizeof(std::thread::id) == 4 || sizeof(std::thread::id) == 8, "std::thread::id is expected to be either 4 or 8 bytes");
 	
@@ -217,7 +217,7 @@ namespace moodycamel { namespace details {
 // VS2013 doesn't support `thread_local`, and MinGW-w64 w/ POSIX threading has a crippling bug: http://sourceforge.net/p/mingw-w64/bugs/445
 // g++ <=4.7 doesn't support thread_local either.
 // Finally, iOS/ARM doesn't have support for it either, and g++/ARM allows it to compile but it's unconfirmed to actually work
-#if (!defined(_MSC_VER) || _MSC_VER >= 1900) && (!defined(__MINGW32__) && !defined(__MINGW64__) || !defined(__WINPTHREADS_VERSION)) && (!defined(__GNUC__) || __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)) && (!defined(__APPLE__) || !TARGET_OS_IPHONE) && !defined(__arm__) && !defined(_M_ARM) && !defined(__aarch64__)
+#if (!defined(_MSC_VER) || _MSC_VER >= 1900) && (!defined(__MINGW32__) && !defined(__MINGW64__) || !defined(__WINPTHREADS_VERSION)) && (!defined(__GNUC__) || __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)) && (!defined(__APPLE__) || !TARGET_OS_IPHONE) && !defined(__arm__) && !defined(_M_ARM) && !defined(__aarch64__) && !defined(__MVS__)
 // Assume `thread_local` is fully supported in all other C++11 compilers/platforms
 #define MOODYCAMEL_CPP11_THREAD_LOCAL_SUPPORTED    // tentatively enabled for now; years ago several users report having problems with it on
 #endif
diff --git a/lightweightsemaphore.h b/lightweightsemaphore.h
index 41ba0943..a0414751 100644
--- a/lightweightsemaphore.h
+++ b/lightweightsemaphore.h
@@ -24,6 +24,8 @@ extern "C" {
 }
 #elif defined(__MACH__)
 #include <mach/mach.h>
+#elif defined(__MVS__)
+#include <zos-semaphore.h>
 #elif defined(__unix__)
 #include <semaphore.h>
 
@@ -165,9 +167,9 @@ class Semaphore
 		}
 	}
 };
-#elif defined(__unix__)
+#elif defined(__unix__) || defined(__MVS__)
 //---------------------------------------------------------
-// Semaphore (POSIX, Linux)
+// Semaphore (POSIX, Linux, zOS)
 //---------------------------------------------------------
 class Semaphore
 {