Re: Finding Circular Dependencies

[Eli Zaretskii]

> From: Paul Smith <address@hidden>
> Cc: Dave Korn <address@hidden>, address@hidden,
>         address@hidden
> Date: Tue, 12 Feb 2008 09:46:34 -0500
> 
> The thing to remember is that GNU make's dependency
> graph is not a single-rooted tree.  It's a set of directed acyclic
> graphs.

I think Graphviz should have no difficulty showing a DAG or a set of
DAGs.

> There isn't really any one starting point inherent in the
> graph.  GNU make starts either (a) where the user asks via command line
> goals, or (b) the first target it finds in the makefiles.

But Make does construct _all_ of the graphs in memory, doesn't it?  It
doesn't construct only those graphs it needs to work with, given the
target(s), right?

> The question is, do you want to construct a graph of the entire set of
> targets that are defined in the makefile?  Because it's quite common for
> there to be a number of completely disjoint graphs.  Or do you want to
> construct a graph for the targets that will actually be checked during a
> given invocation of make?

The latter would be enough, but it would be nice to show all of the
graphs as well.