C++ macro to test availability of __func__, __FUNCTION__, __PRETTY_FUNCTION__, etc

Question

Various modern C/C++ compilers include one or both of __func__ / __FUNCTION__ for purposes of logging the currently executing function. MSVC++ also includes __FUNCSIG__ and GCC __PRETTY_FUNCTION__ as compiler-specific enhanced flavors of this functionality.

GCC defines these as variables rather than macros, however, so it isn't possible to test for their presence via a #ifdef preprocessor directive.

I'm working with a codebase that must work with C++98 and C++11 flavors of MSVC++ and GCC, and the logging facility that someone wrote erroneously tries to test for __FUNCTION__ if __FUNCSIG__ is not available. This check always returns false, rendering function logging support non-operational.

Question: Is there a good macro out there that makes a sufficient-for-my-use-cases guess at which (if any) of these features should be present, possibly by sniffing out compiler versions?

Answer 1

T.C. supplied this answer first, as a comment under my question, and I ended up basing my solution on it:

The header <boost/current_function.hpp> in Boost.Assert implements a BOOST_CURRENT_FUNCTION macro that attempts to map to a suitable "current function" facility provided by the compiler.

Documentation is here:

http://www.boost.org/doc/libs/1_66_0/libs/assert/doc/html/assert.html#current_function_macro_boost_current_function_hpp

And here is a concise reproduction of the macro for reference:

#if defined( BOOST_DISABLE_CURRENT_FUNCTION )
# define BOOST_CURRENT_FUNCTION "(unknown)"
#elif defined(__GNUC__) || (defined(__MWERKS__) && (__MWERKS__ >= 0x3000)) || (defined(__ICC) && (__ICC >= 600)) || defined(__ghs__)
# define BOOST_CURRENT_FUNCTION __PRETTY_FUNCTION__
#elif defined(__DMC__) && (__DMC__ >= 0x810)
# define BOOST_CURRENT_FUNCTION __PRETTY_FUNCTION__
#elif defined(__FUNCSIG__)
# define BOOST_CURRENT_FUNCTION __FUNCSIG__
#elif (defined(__INTEL_COMPILER) && (__INTEL_COMPILER >= 600)) || (defined(__IBMCPP__) && (__IBMCPP__ >= 500))
# define BOOST_CURRENT_FUNCTION __FUNCTION__
#elif defined(__BORLANDC__) && (__BORLANDC__ >= 0x550)
# define BOOST_CURRENT_FUNCTION __FUNC__
#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901)
# define BOOST_CURRENT_FUNCTION __func__
#elif defined(__cplusplus) && (__cplusplus >= 201103)
# define BOOST_CURRENT_FUNCTION __func__
#else
# define BOOST_CURRENT_FUNCTION "(unknown)"
#endif

I ended up modifying the codebase I was working with to use the Boost macro when available, and to fall back to a reasonable subset of the Boost checks otherwise (GCC > MSVC++ > C++11).