[Cmake] Precompiled headers with VC++

[Sebastien BARRE]

At 2/21/2002 10:55 AM, Miller, James V (CRD) wrote:
>Why put the pch files into CVS at all?
>
>Should the build process automatically create these? If a user
>wants to use pch files, they would be generated on their system
>for their use. We would create one/several include files that
>would be transformed into a precompiled header.

Sure.

I mean, Bill Lorensen does not want Perl :) So I suggested to include the 
pch (here I guess you meant this special file header file that is going to 
produce the real pch file) in the CVS. But of course another suggestion 
would be to emulate this Perl script in a CMake command. Should be easy to 
do. And then use that command to create this special pch.

If I remember correctly, Ken coded a nasty command called 
OUTPUT_REQUIRED_FILES that could be used as a starting point.

>What about other systems/compilers?  MSDev is not the only system
>that supports precompiled headers.  If we are going to support
>precompiled headers, we devise a plan that would allow other
>compilers to take advantage of it.

We had this discussion in the past, where basically John Biddiscombe would 
come with a solution for Borland and I'd come with a solution for MSDEV. 
They should be easy to unite, if I remember correctly. Now for the other 
compilers...

>  (All the more reason
>not to include the pch file in CVS).

The pch file might not be the main pb. Another pb is that each CXX file has 
to be updated to include the short piece of code I mentioned before. In the 
past, people thought it was not worth it to include compiler-dependent 
instructions in each CXX file. My opinion is that it's worth it :) Even if 
we can not support all compilers, we can at least support the major ones 
inside #ifdef directives.


--
Sebastien Barre