[Python-Dev] Why is python linked with c++?

Skip Montanaro skip@pobox.com
Wed, 9 Jul 2003 17:09:56 -0500

    >> I think you need different check than the usual command completion to
    >> determine whether -Kthread should be given or not.  If you can
    >> suggest some ways to do this with configure macros I will take a stab
    >> at it, but I don't understand autoconf/configure well enough.  I
    >> suspect doing something like
    >> c++ -Kthread ... 2>&1 >/dev/null | egrep 'unrecognized option'
    >> is too fragile, but that may be the only sort of solution available.

    Martin> It's not necessary to understand autoconf at all. Tell me what
    Martin> algorithm *you* use to determine that -Kthread is a bad idea,
    Martin> and I tell you how to translate it into autoconf.

I used my eyeballs.  gcc/g++ as I've now posted a couple times complains
about the -Kthread flag, but goes on to complete the command and exits with
a 0 status.  A bit of fiddling I did since my last post suggests it doesn't
like -pthread either, at least not on Mac OS X.

    Martin> The current algorithm is not only supposed to find out whether
    Martin> -Kthread is available, but also if it has any effect -
    Martin> i.e. whether providing that option indeed enables the threads
    Martin> library which wouldn't be enabled without it. For some reason,
    Martin> it determines that -Kthread is supported and has the desired
    Martin> effect.

It has the desired effect presumably because -Kthread isn't required.  Gcc
just emits the warning and ignores the flag.