fcppt.config

Description

Compiler, OS and warning related macros.

Introduction Compiler and OS detection Ignoring warnings in external headers Compiler versions

Introduction

fcppt.config contains macros related to the current implementation. This includes which compiler and operating system is being used. Also, there is a set of headers, called external_begin.hpp and external_end.hpp which can be used to ignore warnings in external headers.

Compiler and OS detection

Compiler Detection

In fcppt/config/compiler.hpp several macros may be defined to identify the current compiler:

Macro	Description
FCPPT_CONFIG_GCC_COMPILER	Defined when the compiler is gcc or clang. clang emulates gcc to a large extent.
FCPPT_CONFIG_CLANG_COMPILER	Defined when the compiler is clang.
FCPPT_CONFIG_APPLE_CLANG_COMPILER	Defined when the compiler is the Apple clang compiler (XCode).

OS Detection

In fcppt/config/platform.hpp several macros may be defined to identify the operating system:

Macro	Description
FCPPT_CONFIG_WINDOWS_PLATFORM	Defined on Windows (and MinGW).
FCPPT_CONFIG_UNIX_PLATFORM	Defined on Unix (including Linux).
FCPPT_CONFIG_POSIX_PLATFORM	Defined on POSIX (including Linux).

Ignoring warnings in external headers

There are many possible warning options for different C++ compilers. To improve quality of code, it is advisable to enable as many of them as possible. The downside is that this will also enable a lot of warnings in files that you include but have no control over. fcppt provides a pair of headers, called fcppt/config/external_begin.hpp and fcppt/config/external_end.hpp which can be used to wrap external includes, for example:

#include <fcppt/config/external_begin.hpp>
#include <type_traits>
#include <fcppt/config/external_end.hpp>

To ignore warnings in C headers, fcppt/config/external_begin.h and fcppt/config/external_end.h must be used instead.

Compiler versions

Sometimes it is necessary to detect if a compiler version is greater or equal to a given version. For example, ignoring certain warning options might only work starting from a specific compiler version:

#include <fcppt/config/gcc_version_at_least.hpp>
 
#if FCPPT_CONFIG_GCC_VERSION_AT_LEAST(4, 9) && !FCPPT_CONFIG_GCC_VERSION_AT_LEAST(6, 0)
#include <fcppt/preprocessor/disable_gcc_warning.hpp>
 
FCPPT_PP_DISABLE_GCC_WARNING(-Wfloat-conversion)
#endif

All the macros evaluate to false when on a different compiler, for example FCPPT_CONFIG_GCC_VERSION_AT_LEAST is always false on clang.

The macros are:

Macro	Header
FCPPT_CONFIG_GCC_VERSION_AT_LEAST	fcppt/config/gcc_version_at_least.hpp
FCPPT_CONFIG_CLANG_VERSION_AT_LEAST	fcppt/config/clang_version_at_least.hpp

Macros
#define	FCPPT_CONFIG_CLANG_VERSION_AT_LEAST(major, minor)
	Checks if the clang is being used and its version is at least (major, minor)
#define	FCPPT_CONFIG_GCC_VERSION_AT_LEAST(major, minor)
	Checks if the gcc is being used and its version is at least (major, minor)
#define	FCPPT_CONFIG_MSVC_VERSION_AT_LEAST(version)
	Checks if the msvc is being used and its version is at least version.

Macro Definition Documentation

FCPPT_CONFIG_CLANG_VERSION_AT_LEAST

#define FCPPT_CONFIG_CLANG_VERSION_AT_LEAST	(		major,
			minor )

Value:

FCPPT_CONFIG_DETAIL_CLANG_VERSION_AT_LEAST(\
        major,\
        minor\
)

Checks if the clang is being used and its version is at least (major, minor)

FCPPT_CONFIG_GCC_VERSION_AT_LEAST

#define FCPPT_CONFIG_GCC_VERSION_AT_LEAST	(		major,
			minor )

Value:

FCPPT_CONFIG_DETAIL_GCC_VERSION_AT_LEAST(\
        major,\
        minor \
)

Checks if the gcc is being used and its version is at least (major, minor)

FCPPT_CONFIG_MSVC_VERSION_AT_LEAST

#define FCPPT_CONFIG_MSVC_VERSION_AT_LEAST

(

version

)

Value:

  FCPPT_CONFIG_DETAIL_MSVC_VERSION_AT_LEAST(version)

Checks if the msvc is being used and its version is at least version.