Fix definition of V8_*_C() macros.

include/v8config.h

 // 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 75 matching lines @@
 #endif
 
 
 // -----------------------------------------------------------------------------
 // Compiler detection
 //
 //  V8_CC_CLANG   - Clang
 //  V8_CC_GNU     - GNU C++
 //  V8_CC_INTEL   - Intel C++
 //  V8_CC_MINGW   - Minimalist GNU for Windows
+//  V8_CC_MINGW32 - Minimalist GNU for Windows (mingw32)
+//  V8_CC_MINGW64 - Minimalist GNU for Windows (mingw-w64)
 //  V8_CC_MSVC    - Microsoft Visual C/C++
 //
 // C++11 feature detection
 //
 //  V8_HAS_CXX11_ALIGNAS        - alignas specifier supported
 //  V8_HAS_CXX11_ALIGNOF        - alignof(type) operator supported
 //  V8_HAS_CXX11_STATIC_ASSERT  - static_assert() supported
 //  V8_HAS_CXX11_DELETE         - deleted functions supported
 //  V8_HAS_CXX11_FINAL          - final marker supported
 //  V8_HAS_CXX11_OVERRIDE       - override marker supported
@@ skipping 50 matching lines @@
 
 #elif defined(__GNUC__)
 
 # define V8_GNUC_PREREQ(major, minor, patchlevel)                         \
     ((__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) >=   \
      ((major) * 10000 + (minor) * 100 + (patchlevel)))
 
 # define V8_CC_GNU 1
 // Intel C++ also masquerades as GCC 3.2.0
 # define V8_CC_INTEL (defined(__INTEL_COMPILER))
-# define V8_CC_MINGW (defined(__MINGW32__))
+# define V8_CC_MINGW32 (defined(__MINGW32__))
+# define V8_CC_MINGW64 (defined(__MINGW64__))
+# define V8_CC_MINGW (V8_CC_MINGW32 || V8_CC_MINGW64)
 
 # define V8_HAS___ALIGNOF__ (V8_GNUC_PREREQ(4, 3, 0))
 
 # define V8_HAS_ATTRIBUTE_ALIGNED (V8_GNUC_PREREQ(2, 95, 0))
 // always_inline is available in gcc 4.0 but not very reliable until 4.4.
 // Works around "sorry, unimplemented: inlining failed" build errors with
 // older compilers.
 # define V8_HAS_ATTRIBUTE_ALWAYS_INLINE (V8_GNUC_PREREQ(4, 4, 0))
 # define V8_HAS_ATTRIBUTE_DEPRECATED (V8_GNUC_PREREQ(3, 4, 0))
 # define V8_HAS_ATTRIBUTE_VISIBILITY (V8_GNUC_PREREQ(4, 3, 0))
@@ skipping 178 matching lines @@
 # define V8_ALIGNOF(type) __alignof__(type)
 #else
 // Note that alignment of a type within a struct can be less than the
 // alignment of the type stand-alone (because of ancient ABIs), so this
 // should only be used as a last resort.
 namespace v8 { template <typename T> class AlignOfHelper { char c; T t; }; }
 # define V8_ALIGNOF(type) (sizeof(::v8::AlignOfHelper<type>) - sizeof(type))
 #endif
 
 #endif  // V8CONFIG_H_