Re: [boost] [detail/lightweight_mutex] ODR violation

From: Joaquín Mª López Muñoz (joaquin_at_[hidden])
Date: 2007-09-07 09:46:40

Joaquín Mª López Muñoz ha escrito:

> Peter Dimov ha escrito:
>
> > Joaquín Mª López Muñoz:
> >
> > > boost/detail/flyweight_mutex.hpp implements a mutex class based on a
> > > Win32 CRITICAL_SECTION or using Pthreads according to the
> > > following pp logic:
> > >
> > > #if defined(WIN32) || defined(_WIN32) || defined(__WIN32__)
> > >   // based on CRITICAL_SECTION
> > > #elif defined(BOOST_HAS_PTHREADS)
> > >   // based on Pthreads
> > >
> > > The problem with this is that WIN32 and related macros are not predefined
> > > in some environments (Cygwin at least) but rather they are defined inside
> > > windows.h, thus making the logic above dependent on the inclusion context.
> >
> > Would it help if we reverse the two tests?
>
> AFAICS, yes. The complementary problem (selecting Pthreads in Win32 when
> <pthread.h> has been included) seems not to happen when the logic
> is reversed, at least with pthreads-win32, but further confirmation on this issue
> would be great.

Another option could be to rely upon BOOST_HAS_PTHREADS and
BOOST_HAS_WINTHREADS, as it looks like Boost.Config takes extreme
care to guratnee that they're mutually exclusive. I guess John can shed some light
on this.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo