Fix infinite hang in emscripten_futex_wait

system/lib/pthread/emscripten_futex_wait.c

@@ -224,7 +224,7 @@ int emscripten_futex_wait(volatile void *addr, uint32_t val, double max_wait_ms)
     }
     // If remainder_ns is negative it means we want wait forever, and we don't
     // need to decrement remainder_ns in that case.
-    if (wakeup_interval && remainder_ns > 0) {
+    if (wakeup_interval && remainder_ns >= 0) {
       remainder_ns -= wakeup_interval;
       if (remainder_ns <= 0) {
         break;

test/core/pthread/emscripten_futexes.c → test/core/pthread/emscripten_futex_api_basics.c

@@ -14,6 +14,10 @@ int main() {
   rc = emscripten_futex_wait(&futex_value, futex_value, 1);
   assert(rc == -ETIMEDOUT);
 
+  // As should this.
+  rc = emscripten_futex_wait(&futex_value, futex_value, 0);
+  assert(rc == -ETIMEDOUT);
+
   // Check that this thread has removed itself from the wait queue.
   rc = emscripten_futex_wake(&futex_value, INT_MAX);
   assert(rc == 0);

test/test_core.py

@@ -9251,10 +9251,10 @@ def test_emscripten_atomics(self):
     self.do_core_test('pthread/emscripten_atomics.c', cflags=['-pthread'])
 
   @requires_pthreads
-  def test_emscripten_futexes(self):
+  def test_emscripten_futex_api_basics(self):
     # This test explicitly checks behavior of passing NULL to emscripten_futex_wake() so
     # need to disable the `-Wno-nonnull` to disabled these warnings.
-    self.do_core_test('pthread/emscripten_futexes.c', cflags=['-pthread', '-Wno-nonnull'])
+    self.do_core_test('pthread/emscripten_futex_api_basics.c', cflags=['-pthread', '-Wno-nonnull'])
 
   @requires_pthreads
   def test_stdio_locking(self):