[LLVMdev] [cfe-dev] RFC: Upcoming Build System Changes

Óscar Fuentes ofv at wanadoo.es
Fri Oct 28 15:19:51 PDT 2011

Rafael Ávila de Espíndola <rafael.espindola at gmail.com> writes:

>> BTW, adding explicit library dependencies will make the parallel builds
>> worse, because you know when a dependency is missing (the build fails)
>> but you don't know when a dependency is superfluous.
> Computing the dependencies creates a point in the build that depends on 
> all libraries and all tools depend on it. The explicit dependencies 
> would have to be in a really bad state to be this bad.

First: that's a single point in the build, while superfluous
dependencies may affect almost all points.

Second: if that is a problem, we can get rid of it by changing a single
line [1]. IIRC, it is a remains of the implementation as it was when
first created, when the dependencies were automatically generated and
the build re-started in case of any change. Now it is unncessary.

[1] I'm talking about the state of the cmake build as it was when I
    left. Maybe it was already removed.

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