[cmake-developers] RFC: CMake precompiled header support and custom compiler based implementation

[Brad King]

On 03/13/2015 08:44 AM, Daniel Pfeifer wrote:
> I pushed some work to https://github.com/purpleKarrot/CMake/commits/pch

Thanks for working on this.  I'm hoping others will respond because
I have little experience with PCH.

> target_precompile_headers(bar INTERFACE bar.h)
[snip]
> This command is used to set a list of headers "to precompile".

This would say that any target that links to 'bar' would get 'bar.h' as
a source file to be precompiled for that target's settings.  This makes
some sense for producing the precompiled header, but what decides what
precompiled header is *used* by each source file?  IIUC a given compiler
call may specify at most one precompiled header to use because it is
actually more like a partially compiled translation unit to be continued
by each source consuming it.

Thanks,
-Brad