[CMake] How to guarntee the sequence of build if no target can be used

[Tyler Roscoe]

On Wed, May 27, 2009 at 11:01:51PM +0000, idlecat511 at gmail.com wrote:
> foo.h is generated from foo.x. And foo.h is included by bar.h. And then  
> bar.h is included by a lot of c files. So actually every c files including  
> bar.h depends on foo.h.
> But the file number is so big that I don't want to add dependency for each  
> one.

CMake knows how to resolve these header dependencies. So any file that
#includes (or #includes something that #includes) foo.h will be
recompiled if foo.h changes. You don't need to do anything else for this
part.

> How can I specify foo.x is generated before all the c files being compiled? 
> It seems add_custom_target works but it will regenerate foo.h every time  
> even the foo.x is not modified.

If your custom_target() has correct OUTPUT and DEPENDS parameters, this
should not happen. Are you specifying ALL in your add_custom_target()?

tyler