Revert of Check for semaphore alignment on posix platforms.

src/base/platform/semaphore.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/platform/semaphore.h"
 
 #if V8_OS_MACOSX
 #include <mach/mach_init.h>
 #include <mach/task.h>
 #endif
@@ skipping 56 matching lines @@
     if (result == KERN_SUCCESS) return true;  // Semaphore was signalled.
     if (result == KERN_OPERATION_TIMED_OUT) return false;  // Timeout.
     DCHECK_EQ(KERN_ABORTED, result);
     now = TimeTicks::Now();
   }
 }
 
 #elif V8_OS_POSIX
 
 Semaphore::Semaphore(int count) {
-  // The sem_init() does not check for alignment of the native handle.
-  // Unaligned native handle can later cause a failure in semaphore signal.
-  // Check the alignment here to catch the failure earlier.
-  // Context: crbug.com/605349.
-  const uintptr_t kPointerAlignmentMask = sizeof(void*) - 1;
-  CHECK_EQ(
-      0, reinterpret_cast<uintptr_t>(&native_handle_) & kPointerAlignmentMask);
   DCHECK(count >= 0);
 #if V8_LIBC_GLIBC
   // sem_init in glibc prior to 2.1 does not zero out semaphores.
   memset(&native_handle_, 0, sizeof(native_handle_));
 #endif
   int result = sem_init(&native_handle_, 0, count);
   DCHECK_EQ(0, result);
   USE(result);
 }
 
@@ skipping 112 matching lines @@
       DCHECK(result == WAIT_OBJECT_0);
       return true;
     }
   }
 }
 
 #endif  // V8_OS_MACOSX
 
 }  // namespace base
 }  // namespace v8