"Martin v. Löwis" <[EMAIL PROTECTED]> writes: > David Abrahams wrote: >> - we add a configure test that runs after the existing test >> determines that --with-cxx is needed (but not when --with-cxx is >> explicitly specified on the command line) >> >> - This test runs a 'C' executable that tries to load a C++ dynamic >> library with dlopen. >> >> - The test returns an error code if the the dynamic library's static >> and dynamic initializers have not been run properly >> >> - If the test fails we disable --with-cxx >> >> ?? > > What would be the purpose of such a test? The test may fail for many > reasons, for example, dlopen might not be available.
I was assuming we only disable --with-cxx if the test builds successfully. I presume dlopen will fail linking if it's unavailable? > OTOH, on current Linux systems the test would succeed, so configure > would conclude to link with g++. Uhh, whoops. Change the sense of my last bullet - If the test passes we disable --with-cxx >> I'm trying to intrude on the existing behavior as little as possible, >> yet get the semantics we want for ELF/Linux in a way that stands a >> good chance of generalizing to other platforms. > > I now think that the code should be made more simple, not more complex. > Aspects of a solution I could accept: > > - ccpython.cc and linking with g++ is removed entirely. or, That would be bad for C++ users on HP/UX. Is that acceptable? > - the logic is fixed so that linking with g++ is only done if > main is in ccpython.o I don't see how that works. Somehow we need to decide whether to put main in ccpython.o in the first place, don't we? > - the configure test is extended to better match current g++ > behaviour. What do you have in mind? >> Well, that would certainly be an easy "solution," but it would break >> HP/UX, and it would break anyone that needs to statically link C++ >> modules on some platforms. It's a much more drastic change than it >> would be to only have the system use --with-cxx when the person >> running configure asks for it explicitly. > > I just checked, and it seems that the logic in use is still somewhat > different. If the configure test determines that a C++ main() > must be linked with CXX, it unconditionally changes the linker to CXX. > The test, in turn, is run always if a C++ compiler was found, > i.e. independently of whether --with-cxx was provided. That doesn't match up with reports from my testers who say they can run with C++ extension modules from many different GCC versions if they just configure their Python --without-cxx. If what you were saying were true, wouldn't --without-cxx be ignored on ELF/Linux? -- Dave Abrahams Boost Consulting www.boost-consulting.com _______________________________________________ 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
