OrangesGeneratePlatformHeader

This module provides the function oranges_generate_platform_header() and an extensive set of cache variables describing the current target platform.

The header generation command

oranges_generate_platform_header

oranges_generate_platform_header (<targetName>
                                 [BASE_NAME <baseName>]
                                 [HEADER <headerName>]
                                 [LANGUAGE <CXX|C|OBJCXX|OBJC|Fortran|ASM>]
                                 [SCOPE <PUBLIC|PRIVATE|INTERFACE>]
                                 [INSTALL_COMPONENT <componentName>] [REL_PATH <installRelPath>])

Generates a header file containing various platform identifying macros for the current target platform.

The value of each macro in the generated header file will be set from a corresponding cache variable, which allows the user a high level of configurability, and the ability to override specific details about the current platform as needed. The entire set of cache variables used to store platform attributes is initialized when this module is first included. Thus, you can use this module’s cache variables in your CMake scripts without actually generating a header file.

Options:

BASE_NAME

Prefix to use for all macros in the generated header file. Defaults to <targetName>.

HEADER

Name of the header file to be generated. Defaults to <baseName>_platform.h.

LANGUAGE

Some of the platform introspection requires specifying a language, because some features may be compiler-specific. For these options, the cache variables are suffixed with <lang> (where lang is the language in all-uppercase), so that multiple settings can be saved (and overridden) for different languages. Defaults to the value of the PLAT_DEFAULT_TESTING_LANGUAGE variable.

SCOPE

Scope with which the generated header will be added to the target. Defaults to INTERFACE for interface library targets, PRIVATE for executables, and PUBLIC for all other target types.

INSTALL_COMPONENT

An install component the generated header will be added to. This command will not create the install component.

REL_PATH

Path below CMAKE_INSTALL_INCLUDEDIR where the generated file will be installed to. Defaults to <targetName>.

Macros

The generated file will contain the following macros, where <baseName> and <lang> are all uppercase:

OS type macros

Macro name	Cache variable	Value	Notes
<baseName>_UNIX	PLAT_UNIX	0 or 1
<baseName>_POSIX	PLAT_POSIX	0 or 1
<baseName>_WINDOWS	PLAT_WIN	0 or 1
<baseName>_MINGW	PLAT_MINGW	0 or 1
<baseName>_LINUX	PLAT_LINUX	0 or 1
<baseName>_APPLE	PLAT_APPLE	0 or 1	True if the target platform is any Apple OS
<baseName>_OSX	PLAT_MACOSX	0 or 1	True if the target platform is desktop MacOS.
<baseName>_IOS	PLAT_IOS	0 or 1	True for any iOS-like OS (iOS, tvOS, or watchOS)
<baseName>_ANDROID	PLAT_ANDROID	0 or 1
<baseName>_MOBILE	PLAT_MOBILE	0 or 1	True for iOS, watchOS, or Android
<baseName>_EMBEDDED	PLAT_EMBEDDED	0 or 1	True if the target is an embedded platform. This defaults to true if CMAKE_SYSTEM_NAME is Generic.
<baseName>_OS_TYPE	PLAT_OS_TYPE	String literal	A string literal describing the OS type being run. Defaults to one of ‘MacOSX’, ‘iOS’, ‘tvOS’, ‘watchOS’, ‘Windows’, ‘Linux’, or ‘Android’.

Compiler type macros

Macro name	Cache variable	Value	Notes
<baseName>_CLANG	PLAT_CLANG_<lang>	0 or 1	True if the compiler is Clang or AppleClang
<baseName>_GCC	PLAT_GCC_<lang>	0 or 1
<baseName>_MSVC	PLAT_MSVC_<lang>	0 or 1
<baseName>_INTEL_COMPILER	PLAT_INTEL_COMPILER_<lang>	0 or 1
<baseName>_CRAY_COMPILER	PLAT_CRAY_COMPILER_<lang>	0 or 1
<baseName>_ARM_COMPILER	PLAT_ARM_COMPILER_<lang>	0 or 1
<baseName>_COMPILER_TYPE	PLAT_COMPILER_TYPE_<lang>	String literal	A string literal describing the compiler used. Either Clang, GCC, MSVC, Intel, ARM, Cray, or Unknown

Compiler version macros

Macro name	Cache variable	Value	Notes
<baseName>_COMPILER_VERSION_MAJOR	PLAT_COMPILER_VERSION_MAJOR_<lang>	Numeric literal	Number representing the compiler’s major version, if available; otherwise, 0.
<baseName>_COMPILER_VERSION_MINOR	PLAT_COMPILER_VERSION_MINOR_<lang>	Numeric literal	Number representing the compiler’s minor version, if available; otherwise, 0.
<baseName>_COMPILER_VERSION_PATCH	PLAT_COMPILER_VERSION_PATCH_<lang>	Numeric literal	Number representing the compiler’s patch version, if available; otherwise, 0.
<baseName>_COMPILER_VERSION	PLAT_COMPILER_VERSION_<lang>	String literal	A string literal describing the version of the compiler being used

Processor and architecture macros

Macro name	Cache variable	Value	Notes
<baseName>_ARM	PLAT_ARM	0 or 1
<baseName>_INTEL	PLAT_INTEL	0 or 1
<baseName>_CPU_TYPE	PLAT_CPU_TYPE	String literal	A string literal describing the CPU. Either ARM, Intel, or Unknown
<baseName>_32BIT	PLAT_32BIT	0 or 1
<baseName>_64BIT	PLAT_64BIT	0 or 1
<baseName>_BIG_ENDIAN	PLAT_BIG_ENDIAN_<lang>	0 or 1
<baseName>_LITTLE_ENDIAN	PLAT_LITTLE_ENDIAN_<lang>	0 or 1

SIMD instruction capabilities

Macro name	Cache variable	Value
<baseName>_ARM_NEON	PLAT_ARM_NEON	0 or 1
<baseName>_AVX	PLAT_AVX	0 or 1
<baseName>_AVX512	PLAT_AVX512	0 or 1
<baseName>_SSE	PLAT_SSE	0 or 1

Note

Each macro used by this header file will always be defined to a value, so you should use #if to check their values, and not #ifdef.

Cache variables

PLAT_DISABLE_SIMD

If on, all SIMD-related macros are initialized to 0, instead of attempting to detect features present with the current toolchain and target platform. Defaults to OFF.

PLAT_DEFAULT_TESTING_LANGUAGE

The language that will be used to initialize the values of language- or compiler-specific variables the first time this module is included. Defaults to CXX.

See also

Module OrangesGenerateStandardHeaders

An aggregate module that includes this one