C++定义的宏
|
Macro |
Description |
|---|---|
|
__DATE__ |
The compilation date of the current source file. The date is a string literal of the form Mmm dd yyyy. The month name Mmm is the same as for dates generated by the library function asctimedeclared in TIME.H. |
|
__FILE__ |
The name of the current source file. __FILE__ expands to a string literal. To ensure that the full path to the file is displayed, use /FC (Full Path of Source Code File in Diagnostics). |
|
__func__ |
Returns the unqualified and unadorned name of the enclosing function as an array of char. void Foo(){
printf("%s\n", __func__);
} // prints “Foo”
|
|
__LINE__ |
The line number in the current source file. The line number is a decimal integer literal. It can be changed with a #line directive. |
|
__STDC__ |
Indicates conformance with the ANSI/ISO C99 standard. Defined as the integer literal constant 1 only if the /Za compiler option is given and you are not compiling C++ code; otherwise is undefined. |
|
__TIME__ |
The most recent compilation time of the current source file. The time is a string literal of the formhh:mm:ss. |
|
__TIMESTAMP__ |
The date and time of the last modification of the current source file, expressed as a string literal in the form Ddd Mmm Date hh:mm:ss yyyy, where Ddd is the abbreviated day of the week andDate is an integer from 1 to 31. |
|
Macro |
Description |
|---|---|
|
_ATL_VER |
Defines the ATL version, encoded as an integer literal.
|
|
__AVX__ |
Defined when /arch:AVX or /arch:AVX2 is specified. |
|
__AVX2__ |
Defined when /arch:AVX2 is specified. |
|
_CHAR_UNSIGNED |
Default char type is unsigned. Defined when /J is specified. |
|
__CLR_VER |
Defines the version of the common language runtime used when the application was compiled. The value returned is an integer literal encoded in the following format: Mmmbbbbb where,
// clr_ver.cpp
// compile with: /clr
using namespace System;
int main() {
Console::WriteLine(__CLR_VER);
}
|
|
__cplusplus_cli |
Defined when you compile with /clr, /clr:pure, or /clr:safe. Value of __cplusplus_cli is the integer literal 200406. __cplusplus_cli is in effect throughout the translation unit. // cplusplus_cli.cpp
// compile with: /clr
#include "stdio.h"
int main() {
#ifdef __cplusplus_cli
printf("%d\n", __cplusplus_cli);
#else
printf("not defined\n");
#endif
}
|
|
__cplusplus_winrt |
Defined when you use the /ZW option to compile. The value of __cplusplus_winrt is the integer literal 201009. |
|
__COUNTER__ |
Expands to an integer literal starting with 0 and incrementing by 1 every time it is used in a source file or included headers of the source file. __COUNTER__ remembers its state when you use precompiled headers. The following example uses __COUNTER__ to assign unique identifiers to three different objects of the same type. First, assume the following class definition. The constructor takes an integer as a parameter. // initialize object with a read-only unique ID
exampleClass::exampleClass(int nID)
{
m_nID = nID;
}
int exampleClass::GetID()
{
return m_nID;
}
In main, the application declares three objects of type exampleClass, using __COUNTER__ as the unique identifier parameter. // Demonstration of __COUNTER__, assigns unique identifiers to
// different objects of the same type
int main(int argc, char** argv)
{
// __COUNTER__ is initially defined as 0
exampleClass e1(__COUNTER__);
// having been referenced, __COUNTER__ is now defined as 1
exampleClass e2(__COUNTER__);
// __COUNTER__ is now defined as 2
exampleClass e3(__COUNTER__);
printf("e1 ID: %i\n", e1.GetID());
printf("e2 ID: %i\n", e2.GetID());
printf("e3 ID: %i\n", e3.GetID());
// Output
// ------------------------------
// e1 ID: 0
// e2 ID: 1
// e3 ID: 2
return 0;
}
|
|
__cplusplus |
Defined for C++ programs only. |
|
_CPPRTTI |
Defined for code compiled with /GR (Enable Run-Time Type Information). |
|
_CPPUNWIND |
Defined for code compiled by using one of the /EH (Exception Handling Model) flags. |
|
_DEBUG |
|
|
_DLL |
Defined when /MD or /MDd (Multithreaded DLL) is specified. |
|
__FUNCDNAME__ |
Valid only in a function. Defines the decorated name of the enclosing function as a string literal. __FUNCDNAME__ is not expanded if you use the /EP or /P compiler option. The following example uses the __FUNCDNAME__, __FUNCSIG__, and __FUNCTION__ macros to display function information. // Demonstrates functionality of __FUNCTION__, __FUNCDNAME__, and __FUNCSIG__ macros
void exampleFunction()
{
printf("Function name: %s\n", __FUNCTION__);
printf("Decorated function name: %s\n", __FUNCDNAME__);
printf("Function signature: %s\n", __FUNCSIG__);
// Sample Output
// -------------------------------------------------
// Function name: exampleFunction
// Decorated function name: ?exampleFunction@@YAXXZ
// Function signature: void __cdecl exampleFunction(void)
}
|
|
__FUNCSIG__ |
Valid only in a function. Defines the signature of the enclosing function as a string literal. __FUNCSIG__ is not expanded if you use the /EP or /P compiler option. On a 64-bit operating system, the calling convention is __cdecl by default. See __FUNCDNAME__ for an example. |
|
__FUNCTION__ |
Valid only in a function. Defines the undecorated name of the enclosing function as a string literal. __FUNCTION__ is not expanded if you use the /EP or /P compiler option. See __FUNCDNAME__ for an example. |
|
_INTEGRAL_MAX_BITS |
Reports the maximum size (in bits) for an integral type as an integer literal. // integral_max_bits.cpp
#include <stdio.h>
int main() {
printf("%d\n", _INTEGRAL_MAX_BITS);
}
|
|
_M_AMD64 |
Defined for compilations that target x64 processors. |
|
_M_ARM |
Defined for compilations that target ARM processors. |
|
_M_CEE |
Defined for a compilation that uses any form of /clr (/clr:oldSyntax, /clr:safe, for example). |
|
_M_CEE_PURE |
Defined for a compilation that uses /clr:pure. |
|
_M_CEE_SAFE |
Defined for a compilation that uses /clr:safe. |
|
_M_IX86 |
Defined for compilations that target x86 processors. This is not defined for x64 processors. |
|
_M_ARM_FP |
Expands to an integer literal value indicating which /arch compiler option was used:
|
|
_M_IX86_FP |
Expands to an integer literal value indicating which /arch compiler option was used:
|
|
_M_X64 |
Defined for compilations that target x64 processors. |
|
_MANAGED |
Defined to be 1 when /clr is specified. |
|
_MFC_VER |
Defines the MFC version, encoded as an integer literal. |
|
_MSC_BUILD |
Evaluates to an integer literal that contains the revision number component of the compiler's version number. The revision number is the fourth component of the period-delimited version number. For example, if the version number of the Visual C++ compiler is 15.00.20706.01, the _MSC_BUILD macro evaluates to 1. |
|
_MSC_EXTENSIONS |
This macro is defined when you compile with the /Ze compiler option (the default). Its value, when defined, is 1. |
|
_MSC_FULL_VER |
Evaluates to an integer literal that encodes the major, minor, and build number components of the compiler's version number. The major number is the first component of the period-delimited version number, the minor number is the second component, and the build number is the third component. For example, if the version number of the Visual C++ compiler is 15.00.20706.01, the _MSC_FULL_VER macro evaluates to 150020706. Type cl /? at the command line to view the compiler's version number. |
|
_MSC_VER |
Evaluates to an integer literal that encodes the major and minor number components of the compiler's version number. The major number is the first component of the period-delimited version number and the minor number is the second component. For example, if the version number of the Visual C++ compiler is 17.00.51106.1, the _MSC_VER macro evaluates to 1700. Type cl /? at the command line to view the compiler's version number. |
|
__MSVC_RUNTIME_CHECKS |
Defined when one of the /RTC compiler options is specified. |
|
_MT |
Defined when /MD or /MDd (Multithreaded DLL) or /MT or /MTd (Multithreaded) is specified. |
|
_NATIVE_WCHAR_T_DEFINED |
Defined when /Zc:wchar_t is used. |
|
_OPENMP |
Defined when compiling with /openmp, returns an integer literal representing the date of the OpenMP specification implemented by Visual C++. // _OPENMP_dir.cpp
// compile with: /openmp
#include <stdio.h>
int main() {
printf("%d\n", _OPENMP);
}
|
|
_VC_NODEFAULTLIB |
Defined when /Zl is used; see /Zl (Omit Default Library Name) for more information. |
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_WCHAR_T_DEFINED |
Defined when /Zc:wchar_t is used or if wchar_t is defined in a system header file included in your project. |
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_WIN32 |
Defined for applications for Win32 and Win64. Always defined. |
|
_WIN64 |
Defined for applications for Win64. |
|
_Wp64 |
Defined when specifying /Wp64. |
