[CMake] How to detect & set dependences when build-time(not when cmake)?

[Pedro Lopez-Cabanillas]

On Friday 09 December 2011, 持重 金 wrote:
> Hello every one.
> 
> 
> Recently, I try to rewrite a large project's building system by using cmake.
> I meet a difficult point, how to detect & set dependences when build-time.
> 
> I have lot of this requirement, and currently I solve it with some terrible 
ways. I want some refined ways. For example:
> 
>     Using precompiled header file. 
> 
>         Cmake do not support pch directly and can not detect a header's 
dependences as a source file. 
> 
>         I can't set pch's dependences when cmake-time because it's changed 
frequently and it's dependences is tree structures.

If your PCH changes frequently, then you probably aren't using it correctly. 
The pre-compiled headers should include only stable headers that do not change 
often (for instance: system and 3rd party library headers), because pre-
compiling the PCH file consumes a lot of time and disk space.

Regards,
Pedro