Re: [Boost-build] PCH does not inherit cxxflags (and other parent's requirements)

From: Reece Dunn (msclrhd_at_[hidden])
Date: 2005-12-11 14:12:45

Bojan Resnik wrote:
> Consider the following Jamfile:
> 
> -------
> import cast ;
> 
> exe e : ep e.cpp : <cxxflags>/vmg ;
> pch ep : [ cast _ pcheader : ep.hpp ] ep.cpp ;
> -------
> 
> The precompiled header is compiled without the /vmg compiler switch,
> while the source file is correctly compiled with it.
> 
> It seems that the PCH doesn't inherit any requirements of the project
> that uses it, which often makes it invalid.

Is this the correct behaviour?

Consider:

   pch stdafx : [ cast _ pcheader : stdafx.h ] stdafx.cpp ;

   exe app1 : ... stdafx : <define>HELLO ;
   exe app2 : ... stdafx : <define>WORLD ;

In the above, stdafx would inherit both defines. Would this be the 
required behaviour.

I have not had chance to look into this in depth yet, but the workaround 
to your issue would be to add the arguments to the pch target as well:

   exe e : ep e.cpp : <cxxflags>/vmg ;
   pch ep : [ cast _ pcheader : ep.hpp ] ep.cpp : <cxxflags>/vmg ;

- Reece