Re: multithread CPPFLAGS

[Matthew Woehlke]

Yoann Vandoorselaere wrote:
> Le jeudi 21 août 2008 à 12:28 +0200, Bruno Haible a écrit :
> > Yoann Vandoorselaere wrote:
> > > Most program using the library currently don't (and probably won't)
> > > depend on GnuLib. They are not multithread programs, and in order to
> > > enable the library threaded features, we have to export correct
> > > CFLAGS/LIBS to theses application so that they can compile with
> > > threading enabled.
> > I agree regarding LIBS, but not regarding CPPFLAGS. If the program only
> > ever sees one thread, even though the library uses multiple threads behind
> > its back,
> >   - it does not need to #include <pthread.h>, and
>
> I agree on this one.
>
> >   - it does not need to see a thread-aware errno,
> > hence it does not need to compile with THREADCPPFLAGS.
>
> Not using a thread-aware errno from an application that indirectly use
> thread through a library (which use thread-aware errno). Are you
> completely sure this is safe?

Ah, if the libc uses thread-safe errno and the program doesn't... 
wouldn't that simply break errno? (i.e. libc would set the thread-safe 
errno and the program would get back something different, and thus never 
get the right errno when something goes wrong?) Maybe it would work on 
some platforms, but I'd be really, *really* nervous about it working in 
general.

--
Matthew
Anonymous: I want the following [software] features:
Rex Dieter: ...and a pony. Can't forget the pony. (Ones with frickin' 
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