lack of automatic recompilation after library updating

[Simon Marlow]

Bulat Ziganshin wrote:

> i just reinstalled FPS library with new version downloaded via darcs
> (both old and new versions are 0.7, difference is few days only)
> 
> i run the following to update lib:
> 
> runghc Setup.hs unregister
> runghc Setup.hs clean
> runghc Setup.hs build
> runghc Setup.hs install
> 
> and then i try to rebuild my app. it does not "feels" that FPS library
> was updated and don't recompiled modules that use it. can this be
> considered as bug? ghc 6.4.2/windows

If I understand your description correctly, this is by design.  GHC 
doesn't track version dependencies (in the .hi version sense) across 
package boundaries, which means that if you update a package then code 
that uses the package will not be automatically rebuilt by GHC.  One 
reason for this was to reduce the amount of clutter in .hi files and 
speed up compilation.

Package modules are assumed to be pre-built and static, that's all.

Cheers,
	Simon