diff --git a/tests/pthread/test_pthread_gcc_spinlock.cpp b/tests/pthread/test_pthread_gcc_spinlock.cpp
index ec9c8a2e6..5b23a5ed9 100644
--- a/tests/pthread/test_pthread_gcc_spinlock.cpp
+++ b/tests/pthread/test_pthread_gcc_spinlock.cpp
@@ -1,19 +1,25 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <pthread.h>
-#include <emscripten.h>
+#include <emscripten/emscripten.h>
+#include <emscripten/threading.h>
 #include <unistd.h> // usleep
 #include <assert.h>
 
 volatile int counter = 0; // Shared data
 volatile int lock = 0; // spinlock "mutex" variable
 
+
 void *ThreadMain(void *arg)
 {
 	printf("Thread started.\n");
 	for(int i = 0; i < 100; ++i)
 	{
+#ifdef USE_EMSCRIPTEN_INTRINSICS
+		while(emscripten_atomic_exchange_u32((void*)&lock, 1))
+#else
 		while(__sync_lock_test_and_set(&lock, 1))
+#endif
 		{
 			/*nop*/;
 		}
@@ -21,7 +27,11 @@ void *ThreadMain(void *arg)
 		usleep(5 * 1000); // Create contention on the lock.
 		++c;
 		counter = c;
+#ifdef USE_EMSCRIPTEN_INTRINSICS
+		emscripten_atomic_store_u32((void*)&lock, 0);
+#else
 		__sync_lock_release(&lock);
+#endif
 	}
 	printf("Thread done.\n");
 	pthread_exit(0);
diff --git a/tests/test_browser.py b/tests/test_browser.py
index 00c537944..61b31a185 100644
--- a/tests/test_browser.py
+++ b/tests/test_browser.py
@@ -2542,7 +2542,8 @@ window.close = function() {
 
   # Test the __sync_lock_test_and_set and __sync_lock_release primitives.
   def test_pthread_gcc_spinlock(self):
-    self.btest(path_from_root('tests', 'pthread', 'test_pthread_gcc_spinlock.cpp'), expected='800', args=['-lpthread', '-s', 'PTHREAD_POOL_SIZE=8'])
+    for arg in [[], ['-DUSE_EMSCRIPTEN_INTRINSICS']]:
+      self.btest(path_from_root('tests', 'pthread', 'test_pthread_gcc_spinlock.cpp'), expected='800', args=['-lpthread', '-s', 'PTHREAD_POOL_SIZE=8'] + arg)
 
   # Test that basic thread creation works.
   def test_pthread_create(self):
@@ -2575,7 +2576,7 @@ window.close = function() {
   # Tests the pthread mutex api.
   def test_pthread_mutex(self):
     for arg in [[], ['-DSPINLOCK_TEST']]:
-      self.btest(path_from_root('tests', 'pthread', 'test_pthread_mutex.cpp'), expected='50', args=['-lpthread', '-s', 'PTHREAD_POOL_SIZE=8'])
+      self.btest(path_from_root('tests', 'pthread', 'test_pthread_mutex.cpp'), expected='50', args=['-lpthread', '-s', 'PTHREAD_POOL_SIZE=8'] + arg)
 
   # Test that memory allocation is thread-safe.
   def test_pthread_malloc(self):