David Abrahams wrote: > Apparently Python on some linux distros is being linked by g++ rather > than gcc, resulting in the C++ runtime library being linked into > Python; this has bad consequences for compatibility between C++ > extension modules and Pythons that have been built with different > versions of GCC. Is this behavior intentional?
It's as Skip says. According to the C++ standard, a "C++ program" is one where all translation units are written in C++. While most platforms offer interoperability between C and C++ in the sense that C libraries can be linked into C++ programs, interoperability in the other direction is not always supported, i.e. C programs may not be able to use C++ libraries. This is the specific case you are talking about: Python is written in C, yet the extension might be written in C++. Now, on some of these implementations, things can be fixed by writing main() as a C++ translation unit, and compiling it with the C++ compiler. Then, Python itself is a C library to this C++ program, and the extension modules are C++ libraries. Then everything works fine. To support this, main() must be a C++ program. Python compiles main using the C++ compiler if configure thinks this is necessary. Doing so is necessary for example on systems using the G++ collect2 mechanism for static initializers: compiling main with g++ leads to a call to __main(), which is then created by collect2. configure thinks that using CXX for linking is necessary if compiling a program using CXX and linking it using CC fails. Regards, Martin _______________________________________________ Python-Dev mailing list Python-Dev@python.org http://mail.python.org/mailman/listinfo/python-dev Unsubscribe: http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
