[CMake] Interference between siblings

[Weiguang Guan]

On Fri, 8 Oct 2004, Brad King wrote:

> Weiguang Guan wrote:
> 
> > Hi CMake users,
> > 
> > Variables, include paths, library paths, etc. are inherited from top-level 
> > directory to subdirectories. If we follow this philosophy sibling 
> > directories shouldn't affect one another. However, I find this is not the 
> > case. 
> > 
> > I have a source tree, which looks like
> > 
> > src 
> >     / libraries 
> > 		/ vtk
> > 		/ itk
> > 		/ ...
> >     / apps	
> > 		/ app1 
> > 		/ app2
> > 
> > where CMakeLists.txt in a non-leaf directory contains nothing but 
> > SUBDIRS(...). Then I create a directory 'build' to be the root of build 
> > tree. In the build directory I ccmake ....../src, then the build tree is 
> > generated, which looks like
> > 
> > build
> >     / libraries
> >                 / vtk
> >                 / itk
> >                 / ...
> >     / apps
> >                 / app1
> >                 / app2
> > 
> > Take the Makefile for app1 as an example. It is different from the 
> > Makefile generated by using ccmake ....../src/apps/app1.
> 
> This is because CMake never looks above the directory specified as the 
> top level source tree.  In your example when you specify src/apps/app1 
> as the source tree then it does not inherit any settings from 
> src/CMakeLists.txt or src/apps/CMakeLists.txt.  When you specify src as 
> the source tree then app1 gets all those settings.
> 
> -Brad
> 

I mentioned in my last email that src/CMakeLists.txt and 
src/apps/CMakeLists.txt contain nothing but SUBDIRS.

Weiguang