VC ++ prefix

Microsoft-specific

Note:Both the 16-bit and 32-bit compilers support these macros.

   Macro               Specifies   ------------------------------------------------------------------   _CHAR_UNSIGNED      Default char type is unsigned. Macro defined                       when /J is specified.   M_I86,  _M_I86      Always defined. Identifies target machine as a                       member of the 8086 family.   _MSC_VER            Microsoft C version; currently defined as 800.

The following symbols are added to C/C ++ 7.0:

   Macro               Specifies   --------------------------------------------------------------------   __cplusplus         Macro defined when compiling a C++ program. (This                       macro is not defined for the C compiler.)

Microsoft-specific

   Macro               Specifies   -------------------------------------------------------------------   MSDOS, _MSDOS       Always defined. Identifies target operating system                       as MS-DOS.   M_I86mM, _M_I86mM   Always defined. Member of the I86 processor family.                       Memory model type:                       m = T   Tiny                       S   Small (default)                       C   Compact model                       M   Medium model                       L   Large model                       H   Huge model                       Macros defined by /AT, /AS, /AC, /AM, /AL, and /AH                       respectively.   M_I8086, _M_I8086   8088 or 8086 processor; default or defined when /G0                       is specified.   M_I286, _M_I286     80286 processor. Macro defined when /G1 or /G2 is                       specified.   NO_EXT_KEYS         Disables Microsoft-specific language extensions                       and extended keywords; defined only with /Za                       option.   _QC                 Supported for compatibility with Microsoft C version                       6.0. The _FAST macro (or /f) is the default and is                       the recommended alternative.

The following symbols are added to C/C ++ 7.0:

   Macro               Specifies   -------------------------------------------------------------------   _DLL                Code for run-time library as a dynamic-link library.                       Defined when /MD is specified.   _FAST               Fast-Compile. Macro defined when /f is specified                       Supersedes _QC, which is still supported but not                       recommended. Using /Od causes CL to compile your                       program with /f. The /f option compiles source files                       without any default optimizations.   __STDC__            Full conformance with the ANSI C standard. Defined                       the integer constant 1 only if the /Za command-line                       option is given; otherwise is undefined.   _PCODE              Defined for sections of code that are compiled as                       p-code. Macro defined when /Oq is enabled.   _WINDLL             Windows protected-mode dynamic-link library is                       selected with /GD.   _WINDOWS            Windows protected-mode is selected with /GA, /Gw,                       /GW, /Mq, or /GD.

16-bit special

The following symbols are added to Visual C ++ and 32-bit version 1.0:

   Macro               Specifies   -----               ---------   _DLL                Defined when Multithreaded using DLL (/MD or /MDd)                       is specified.   _M_IX86             Defined as 300 for the 80386 processor (/G3 option),                       as 400 for the 80486 (/G4) processor, as 500                       for the Pentium processor (/G5), and as 600 for                        Pentium Pro and Pentium II processors (/G6).   _MT                 Defined when Multithreaded (/MD, /MDd, /MT, or /MTd)   _WIN32              Defined for WIN32 applications. Always defined.                       Microsoft specific.

The following symbols added to Visual C ++, 32-bit version 4.0:

   Macro               Specifies   -----               ---------   _CPPRTTI            Defined for code compiled with Enable Run-Time Type                       Information (/GR).   _CPPUNWIND          Defined for code compiled with Enable Exception                       Handling (/GX).

_ Msc_ver Macro will have one of the following values depending on a specific Microsoft Compiler:

   Compiler                           _MSC_VER value   --------                           --------------   C Compiler version 6.0                  600   C/C++ compiler version 7.0              700   Visual C++, Windows, version 1.0        800   Visual C++, 32-bit, version 1.0         800   Visual C++, Windows, version 2.0        900   Visual C++, 32-bit, version 2.x         900   Visual C++, 32-bit, version 4.0         1000   Visual C++, 32-bit, version 5.0         1100   Visual C++, 32-bit, version 6.0         1200

NotesIf the predefined identifier has two forms of use and does not use underscores, the command line driver defines two options if/Ze is specified (for Microsoft extension compilation ). If you specify the/za option (compiling ANSI compatibility), it defines only the leading underline form.