Move OS/compiler/feature detection to public v8config.h header.

include/v8.h

 // Copyright 2012 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 25 matching lines @@
  */
 
 #ifndef V8_H_
 #define V8_H_
 
 #include "v8stdint.h"
 
 // We reserve the V8_* prefix for macros defined in V8 public API and
 // assume there are no name conflicts with the embedder's code.
 
-#ifdef _WIN32
+#ifdef V8_OS_WIN
 
 // Setup for Windows DLL export/import. When building the V8 DLL the
 // BUILDING_V8_SHARED needs to be defined. When building a program which uses
 // the V8 DLL USING_V8_SHARED needs to be defined. When either building the V8
 // static library or building a program which uses the V8 static library neither
 // BUILDING_V8_SHARED nor USING_V8_SHARED should be defined.
 #if defined(BUILDING_V8_SHARED) && defined(USING_V8_SHARED)
 #error both BUILDING_V8_SHARED and USING_V8_SHARED are set - please check the\
   build configuration to ensure that at most one of these is set
 #endif
 
 #ifdef BUILDING_V8_SHARED
-#define V8_EXPORT __declspec(dllexport)
+# define V8_EXPORT __declspec(dllexport)
 #elif USING_V8_SHARED
-#define V8_EXPORT __declspec(dllimport)
+# define V8_EXPORT __declspec(dllimport)
 #else
-#define V8_EXPORT
+# define V8_EXPORT
 #endif  // BUILDING_V8_SHARED
 
-#else  // _WIN32
+#else  // V8_OS_WIN
 
 // Setup for Linux shared library export.
-#if defined(__GNUC__) && ((__GNUC__ >= 4) || \
-    (__GNUC__ == 3 && __GNUC_MINOR__ >= 3)) && defined(V8_SHARED)
-#ifdef BUILDING_V8_SHARED
-#define V8_EXPORT __attribute__ ((visibility("default")))
+#if V8_HAS_ATTRIBUTE_VISIBILITY && defined(V8_SHARED)
+# ifdef BUILDING_V8_SHARED
+#  define V8_EXPORT __attribute__ ((visibility("default")))
+# else
+#  define V8_EXPORT
+# endif
 #else
-#define V8_EXPORT
-#endif
-#else
-#define V8_EXPORT
+# define V8_EXPORT
 #endif
 
-#endif  // _WIN32
-
-#if defined(__GNUC__) && !defined(DEBUG)
-#define V8_INLINE(declarator) inline __attribute__((always_inline)) declarator
-#elif defined(_MSC_VER) && !defined(DEBUG)
-#define V8_INLINE(declarator) __forceinline declarator
-#else
-#define V8_INLINE(declarator) inline declarator
-#endif
-
-#if defined(__GNUC__) && !V8_DISABLE_DEPRECATIONS
-#define V8_DEPRECATED(declarator) declarator __attribute__ ((deprecated))
-#elif defined(_MSC_VER) && !V8_DISABLE_DEPRECATIONS
-#define V8_DEPRECATED(declarator) __declspec(deprecated) declarator
-#else
-#define V8_DEPRECATED(declarator) declarator
-#endif
-
-#if __GNUC__ > 2 || (__GNUC__ == 2 && (__GNUC_MINOR__ > 95))
-  #define V8_UNLIKELY(condition) __builtin_expect((condition), 0)
-  #define V8_LIKELY(condition) __builtin_expect((condition), 1)
-#else
-  #define V8_UNLIKELY(condition) (condition)
-  #define V8_LIKELY(condition) (condition)
-#endif
+#endif  // V8_OS_WIN
 
 /**
  * The v8 JavaScript engine.
  */
 namespace v8 {
 
 class AccessorInfo;
 class AccessorSignature;
 class Array;
 class Boolean;
@@ skipping 6487 matching lines @@
  */
 
 
 }  // namespace v8
 
 
 #undef TYPE_CHECK
 
 
 #endif  // V8_H_