We can't use pthread_condattr_setclock() in NaCl.

src/platform/condition-variable.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 23 matching lines @@
 
 namespace v8 {
 namespace internal {
 
 #if V8_OS_POSIX
 
 ConditionVariable::ConditionVariable() {
   // TODO(bmeurer): The test for V8_LIBRT_NOT_AVAILABLE is a temporary
   // hack to support cross-compiling Chrome for Android in AOSP. Remove
   // this once AOSP is fixed.
-#if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || V8_LIBC_GLIBC) && \
-    !V8_LIBRT_NOT_AVAILABLE
+#if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || \
+     (V8_OS_LINUX && V8_LIBC_GLIBC)) && !V8_LIBRT_NOT_AVAILABLE
   // On Free/Net/OpenBSD and Linux with glibc we can change the time
   // source for pthread_cond_timedwait() to use the monotonic clock.
   pthread_condattr_t attr;
   int result = pthread_condattr_init(&attr);
   ASSERT_EQ(0, result);
   result = pthread_condattr_setclock(&attr, CLOCK_MONOTONIC);
   ASSERT_EQ(0, result);
   result = pthread_cond_init(&native_handle_, &attr);
   ASSERT_EQ(0, result);
   result = pthread_condattr_destroy(&attr);
@@ skipping 44 matching lines @@
   // not depend on the real time clock, which is what you really WANT here!
   ts = rel_time.ToTimespec();
   ASSERT_GE(ts.tv_sec, 0);
   ASSERT_GE(ts.tv_nsec, 0);
   result = pthread_cond_timedwait_relative_np(
       &native_handle_, &mutex->native_handle(), &ts);
 #else
   // TODO(bmeurer): The test for V8_LIBRT_NOT_AVAILABLE is a temporary
   // hack to support cross-compiling Chrome for Android in AOSP. Remove
   // this once AOSP is fixed.
-#if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || V8_LIBC_GLIBC) && \
-    !V8_LIBRT_NOT_AVAILABLE
+#if (V8_OS_FREEBSD || V8_OS_NETBSD || V8_OS_OPENBSD || \
+     (V8_OS_LINUX && V8_LIBC_GLIBC)) && !V8_LIBRT_NOT_AVAILABLE
   // On Free/Net/OpenBSD and Linux with glibc we can change the time
   // source for pthread_cond_timedwait() to use the monotonic clock.
   result = clock_gettime(CLOCK_MONOTONIC, &ts);
   ASSERT_EQ(0, result);
   Time now = Time::FromTimespec(ts);
 #else
   // The timeout argument to pthread_cond_timedwait() is in absolute time.
   Time now = Time::NowFromSystemTime();
 #endif
   Time end_time = now + rel_time;
@@ skipping 214 matching lines @@
   // Release the wait event.
   ASSERT(!result || event->notified_);
   native_handle_.Post(event, result);
 
   return result;
 }
 
 #endif  // V8_OS_POSIX
 
 } }  // namespace v8::internal