The macros identified in this section are provided to allow
customers to write programs that use IBM C and C++ Compilers
services. Only those macros identified in this section should be
used to request or receive IBM C and C++ Compilers services.
These macros are in addition to the ANSI predefined macros.
| Macro |
Description |
  __32BIT__ |
Set to the integer 1.
Indicates the product is a 32-bit compiler. |
  __64BIT__ |
Defined when compiling 64 bit programs. |
| _AIX |
Indicates that the
operating system is AIX. |
| _AIX32 |
Indicates that the
operating system is AIX version 3.2 or higher. |
| _AIX41 |
Indicates that the
operating system is AIX version 4.1 or higher. |
| _AIX43 |
Indicates that the operating system is
AIX version 4.3 or higher. |
| __ANSI__ |
Allows only language constructs that
conform to ISO/ANSI C standard. Defined using the #pragma
langlvl directive or /Sa option (Intel). On AIX, the
compiler option is -qlanglvl=(ansi). |
| _ARCH_* |
Indicates that the
compiler generates code to run on the processor or family
of processors denoted by the wildcard (*). E.g.:
_ARCH_PENTIUM2, _ARCH_PWR. Use the -qarch compiler
option. |
| _CHAR_SIGNED |
Indicates default character type is
signed. Defined when the #pragma chars(signed) directive
is in effect, or when the /J- compiler option (Intel) is
set. Use the -qchar=signed option on AIX. |
| _CHAR_UNSIGNED |
Indicates default character type is
unsigned. Defined when the #pragma chars(unsigned)
directive is in effect, or when the /J+ compiler option
(Intel) is set. Use the -qchar=unsigned option on AIX. |
 __COMPAT__ |
Indicates language constructs compatible with earlier
versions of the C++ language are allowed. Defined using
the #pragma langlvl(compat) directive or /Sc compiler
option (Intel). On AIX, the compiler option is
-qlanglvl=(compat). |
| __DBCS__ |
Indicates DBCS support is enabled.
Defined using the /Sn compiler option. |
| __DDNAMES__ |
Indicates ddnames are supported. Defined using the
/Sh compiler option. |
| __DEBUG_ALLOC__ |
Maps memory management functions to
their debug versions. Defined using the /Tm compiler
option (Intel). |
| __DIGRAPHS__ |
|
| __DLL__ or
_DLL |
Indicates code for a DLL is being
compiled. Defined using the /Ge- compiler option. |
| __EXTENDED__ |
Allows additional
language constructs provided by the IBM C and C++
Compilers implementation. Defined using
the #pragma langlvl directive or /S2 option (Intel). On
AIX, the compiler option is -qlanglvl=(extended). |
| _FP_INLINE_
|
Generates inline instructions for the
following floating-point library functions, as defined in
math.h, when targetting an Intel processor: fcos(),
fsin(), fptan(), facos(), fasin(), fpatan(), and fsqrt(). |
| __FUNCTION__ |
Indicates the name of the
function currently being compiled. For C++ programs,
expands to the actual function prototype. |
| __HHW_INTEL__ |
Indicates that the host hardware is an
Intel processor. |
| __HHW_RS6000__ |
Indicates that the host hardware is an RISC 6000
processor. |
|
__HOS_AIX__ |
Indicates that the host
operating system is AIX. |
|
__HOS_OS2__ |
Indicates that the host
operating system is OS/2. |
|
__HOS_WIN__ |
Indicates that the host
operating system is Windows. |
| __IBMC__ |
Indicates the version number of the C compiler.
__IBMC__ = 430. This macro should be used in new code. |
| __IBMCPP__
|
Indicates the version number of the C++ compiler.
__IBMCPP__ = 360. This macro should be used in new code. |
| __IMPORTLIB__ |
Indicates that dynamic linking is used.
Defined using the /Gd option. |
| _LONG_LONG |
Macro defined when the
compiler is in a mode that permits long long int and
unsigned long long int types. |
__LONGDOUBLE128
__LONGDOUBLE80 |
Sets the number of bits
to use when representing the value of a long double.
Under AIX, the available options are 128 and 64 bits.
Under OS/2 and Windows, the available options are 80 and
64 bits. |
| _M_I386 |
Indicates code is being
compiled for a 386 chip or higher. |
| _M_IX86 |
Indicates code is being
compiled for a 386 chip or higher. |
|
__MATH__ |
Instructs the compiler to
generate substitute code for calls to some math functions
available in the standard C runtime libraries, if
appropriate. The functions handled this way are defined
as replacement text for macros that begin with two
underscores (__) in the math.h header file. |
| __MULTI__
or _MT |
Indicates multithread code is being
generated. Defined using the /Gm compiler option. |
| __NO_DEFAULT_LIBS__
|
Indicates that information about default
libraries will not be included in object files. Defined
using the /Gn option. |
| __OS2__ |
Set to the integer 1.
Indicates the product is an OS/2 compiler. |
| _POWER |
Indicates that the
operating system is AIX version 4.1 or higher |
|
__SAA__ |
Allows only language constructs that
conform to the most recent level of SAA C standards.
Defined using the #pragma langlvl directive or /S2 option
(Intel). On AIX, the compiler option is -qlanglvl=(saa). |
|
__SAAL2__ |
Allows only language constructs that
conform to SAA Level 2 C standards. Defined using the
#pragma langlvldirective or /S2 option (Intel). On AIX,
the compiler option is -qlanglvl=(saal2). |
| __SPC__ |
Indicates the subsystem libraries are
being used. Defined using the /Rn compiler option. |
|
_STDCALL_SUPPORTED |
Indicates that the
compiler supports __stdcall linkage. |
| __STR__ |
Instructs the compiler to
generate substitute code for calls to some string
functions available in the standard C runtime libraries,
if appropriate. The functions handled this way are
defined as replacement text for macros that begin with
two underscores (__) in the string.h
header file. |
| __TEMPINC__ |
Indicates the template-implementation file method of
resolving template functions is being used. Defined using
the /Ft compiler option (Intel). |
| __THW_INTEL__ |
Indicates that the target hardware is an Intel
processor. |
| __THW_RS6000__ |
Indicates that the target hardware is a RISC 6000
processor. |
| __TILED__ |
Indicates tiled memory is being used. Defined using
the /Gt compiler option. |
| __TOS_AIX__ |
Indicates that the target
operating system is AIX. |
| __TOS_OS2__ |
Indicates that the target
operating system is OS/2. |
| __TOS_WIN__ |
Indicates that the target
operating system is Windows. |
| _WIN32 |
Indicates that the
compiler generates Win32 code. |
|
__WINDOWS__ |
Set to the integer 1.
Indicates the product is a Windows compiler. |
| __xlC__ |
Use the __IBMC__ and
__IBMCPP__ macros instead. Indicates
a hexadecimal constant with the version and release
number of the compiler. Is in the form:
0xVVRR
where:
VV represents the compiler version
number
RR represents the compiler release number
Has a value of 0x0306 for C++, and
0x0403 for C.
|
