編譯器中和64位編程有關的預定義宏

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本文對分別測試VC，MinGW，GCC 三種編譯器，32位和64位元模式，共6種情況下，和64位編程有關的與預定義宏的值。對跨平台編程具有參考意義。

 

Agner Fog 在他的《Calling conventions for different C++ compilers and operating systems》提到一些預訂宏。這裡摘錄如下。

註：下面的內容來自《Calling conventions for different C++ compilers and operating systems》,Last updated 2012-02-29，By Agner Fog. Copenhagen University College .如何原文內容不符，以原文為準。

 

Most C++ compilers have a predefined macro containing the version number of the
compiler. Programmers can use preprocessing directives to check for the existence of these
macros in order to detect which compiler the program is compiled on and thereby fix
problems with incompatible compilers.

Table 23. Compiler version predefined macros

 

Compiler	Predefined macro
Borland	__BORLANDC__
Codeplay VectorC	__VECTORC__
Digital Mars	__DMC__
Gnu	__GNUC__
Intel	__INTEL_COMPILER
Microsoft	_MSC_VER
Pathscale	__PATHSCALE__
Symantec	__SYMANTECC__
Watcom	__WATCOMC__

 

 Unfortunately, not all compilers have well-documented macros telling which hardware
platform and operating system they are compiling for. The following macros may or may not
be defined:

Table 24. Hardware platform predefined macros

 

platform	Predefined macro
x86	_M_IX86	__INTEL__	__i386__
x86-64	_M_X64	__x86_64__	__amd64
IA64	__IA64__
DEC Alpha	__ALPHA__
Motorola Power PC	__POWERPC__
Any little endian	__LITTLE_ENDIAN__
Any big endian	__BIG_ENDIAN__

 

 

Table 25. Operating system predefined macros

 

Operating system	Predefined macro
DOS 16 bit	__MSDOS__	_MSDOS
Windows 16 bit	_WIN16
Windows 32 bit	_WIN32	__WINDOWS__
Windows 64 bit	_WIN64	_WIN32
Linux 32 bit	__unix__	__linux__
Linux 64 bit	__unix__	__linux__	__LP64__	__amd64
BSD	__unix__	__BSD__	__FREEBSD__
Mac OS	__APPLE__	__DARWIN__	__MACH__
OS/2	__OS2__

 

 

下面的代碼主要測試和64編程有關的宏

void test(){int len=sizeof(int)*8;printf("sizeof(int)=%d\n",len);len=sizeof(int *)*8;printf("sizeof(int*)=%d\n",len);#ifdef _MSC_VERprintf("_MSC_VER is defined\n");#endif#ifdef __GNUC__printf("__GNUC__ is defined\n");#endif#ifdef __INTEL__ printf("__INTEL__  is defined\n");#endif#ifdef __i386__ printf("__i386__  is defined\n");#endif#ifdef __x86_64__ printf("__x86_64__  is defined\n");#endif#ifdef _WIN32 printf("_WIN32 is defined\n");#endif#ifdef _WIN64 printf("_WIN64 is defined\n");#endif#ifdef __linux__ printf("__linux__ is defined\n");#endif#ifdef __LP64__ printf("__LP64__ is defined\n");#endif#ifdef __amd64 printf("__amd64 is defined\n");#endif}int main(int argc, char* argv[]){test();return 0;}