Re: [Boost-build] [PING] State of PCH/msvc

From: Vladimir Prus (ghost_at_[hidden])
Date: 2006-04-26 08:24:10

On Wednesday 26 April 2006 16:19, Phillip Seaver wrote:
> Vladimir Prus wrote:
> > On Wednesday 26 April 2006 16:07, Janssen, Olaf  ST/HZA-TBE wrote:
> >>> PCH is nowhere close to "release" state. There are numerous
> >>> issues with
> >>> PCH on MSVC:
> >>>
> >>> 6. Some other subtle issues I can't remember.
> >>
> >> parallel build does not work (that might also be difficult to implement)
> >
> > What are specific issues with parallel build? There should be a
> > dependency from exe to the used pch, to PCH should be created before exe
> > is compiled?
> >
> > Or the problem is that two copies of compiler try to use the same PCH?
> > It's possible to serialize execution of compile actions for that case.
> >
> > - Volodya
>
> The latter.  You run into the same problem with .pdb files, which is one
> reason I haven't finished it.  I just run without -j2 for those builds.
> Would the serialization force it to do a single thread (even if I had
> -j2) or would it build a separate target that didn't use the same file?

It would serialize compilation of all cpp files that use a single file. 
Creating a second PCH copy sounds non-trivial task.

- Volodya

-- 
Vladimir Prus
http://vladimir_prus.blogspot.com
Boost.Build V2: http://boost.org/boost-build2