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Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc)

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Le 04/06/11 07:32, Gordon Burditt a écrit :
>>> The same issue occurs with the Microsoft C Runtime and C99 printf
>>> support. You can compile 'printf( "%lu %zu\n", sizeof (int), sizeof
>>> (int) );' with gcc -std=c99 in the MinGW environment, but because it
>>> links in the Microsoft Runtime, the printf statement just generates "4
>>> zu". Similar problems occur for modifiers 't' and 'll'.
>>
>> Which raises the question - why do we do that?  Is there some reason
>> why the compilers never seem to supply the equivalent of libc?  Sure,
>
> The interfaces between libc and the rest of the OS (not the interface
> between libc and the user program) may not be documented and changes
> may not be announced.  (I'm thinking especially of the syscall
> interface to the kernel).  This isn't too bad if the OS version of
> libc is open-source, but the compiler vendor needs to track OS
> changes.  Someone who tries to duplicate that may be operating in
> constant catch-up mode to keep up with the changes.  The OS developers
> figure that THEY are in charge of libc and if they make a change
> that stays compatible (e.g. a matching libc/kernel change that won't
> affect dynamic-linked programs, which works great unless you try
> to use an OLD libc on a NEW kernel or vice-versa) they aren't going
> to worry about that other libc some compiler vendor added.
>
> This is less of an issue with math functions, *printf, and the
> string library and such since they usually don't have much of an
> interface with the kernel in areas where changes occur.
>

Exactly, and those functions should be provided by the compiler,
not the OS.

> However, it's a problem trying to replace *PART* of libc.
> Things also tend to go very badly if you try to link to multiple
> versions of the same library.
>

This is absolutely no problem if the linker links to a compiler
version of the libc that THEN calls the OS libc if necessary.
>
>> there are going to be instances where one can get away with using the
>> native OS libc, but clearly there are lots of other cases where it
>> doesn't work out so well.  And I would wager it works out less and
>> less well as the target OS ages.
>
> I can see problems where the OS (and its version of libc) is young
> enough to be under active development.
>

Bogus, since the libc interfaces didn't change since C89 in most
cases.

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OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-02 13:52 -0700
  Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Nobody <nobody@nowhere.com> - 2011-06-02 22:16 +0100
  Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-02 14:18 -0700
    Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-02 14:37 -0700
      Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-03 09:59 +1200
        Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-02 15:18 -0700
          Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-03 10:35 +1200
            Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-02 16:01 -0700
              Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) ImpalerCore <jadill33@gmail.com> - 2011-06-03 06:45 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-03 12:13 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) jacob navia <jacob@spamsink.net> - 2011-06-03 21:35 +0200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-04 08:48 +1200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Nobody <nobody@nowhere.com> - 2011-06-03 23:28 +0100
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) gordonb.myhxj@burditt.org (Gordon Burditt) - 2011-06-04 00:32 -0500
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) jacob navia <jacob@spamsink.net> - 2011-06-04 08:06 +0200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) gordonb.c5zg9@burditt.org (Gordon Burditt) - 2011-06-04 22:03 -0500
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-05 15:47 +1200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) jacob navia <jacob@spamsink.net> - 2011-06-05 09:48 +0200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-05 20:22 +1200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) jacob navia <jacob@spamsink.net> - 2011-06-05 15:59 +0200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) "Joel C. Salomon" <joelcsalomon@gmail.com> - 2011-06-06 09:09 -0400
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) jacob navia <jacob@spamsink.net> - 2011-06-06 15:24 +0200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-06 10:17 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-07 07:46 +1200
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-09 09:35 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Keith Thompson <kst-u@mib.org> - 2011-06-09 11:18 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) David Mathog <dmathog@gmail.com> - 2011-06-09 12:52 -0700
                Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Ian Collins <ian-news@hotmail.com> - 2011-06-10 09:14 +1200
            Re: OT: missing C99 math pieces in gcc 4.x on Solaris 8 (sparc) Keith Thompson <kst-u@mib.org> - 2011-06-02 16:04 -0700

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