wtf/CheckedArithmetic.h delegates to base/numerics/safe_math.h.

third_party/WebKit/Source/wtf/StdLibExtras.h

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 10 matching lines @@
  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #ifndef WTF_StdLibExtras_h
 #define WTF_StdLibExtras_h
 
 #include "wtf/Assertions.h"
 #include "wtf/CPU.h"
-#include "wtf/CheckedArithmetic.h"
+#include "wtf/CheckedNumeric.h"
 #include "wtf/LeakAnnotations.h"
 #include <cstddef>
 
 #if ENABLE(ASSERT)
 #include "wtf/Noncopyable.h"
 #include "wtf/Threading.h"
 
 class WTF_EXPORT StaticLocalVerifier {
     WTF_MAKE_NONCOPYABLE(StaticLocalVerifier);
 public:
@@ skipping 104 matching lines @@
         FROM from;
         TO to;
     } u;
     u.from = from;
     return u.to;
 }
 
 template<typename To, typename From>
 inline To safeCast(From value)
 {
-    RELEASE_ASSERT(isInBounds<To>(value));
-    return static_cast<To>(value);
+    CheckedNumeric<To> checked(value);
+    return checked.ValueOrDie();

[dcheng, 2016/03/17 08:25:14]

checked_cast is the //base/numerics/safe_conversions.h equivalent.

[Bret, 2016/03/18 20:48:51]

Done.

 }
 
 // Use the following macros to prevent errors caused by accidental
 // implicit casting of function arguments.  For example, this can
 // be used to prevent overflows from non-promoting conversions.
 //
 // Example:
 //
 // HAS_STRICTLY_TYPED_ARG
 // void sendData(void* data, STRICTLY_TYPED_ARG(size))
@@ skipping 34 matching lines @@
 inline void* operator new(size_t, NotNullTag, void* location)
 {
     ASSERT(location);
     return location;
 }
 
 using WTF::bitwise_cast;
 using WTF::safeCast;
 
 #endif // WTF_StdLibExtras_h