Re: XML dumping and GraphViz/VCG in the GCC ast-optimizer-branch

[Joe Buck <jbuck@synopsys.com>]

James Michael DuPont writes:

> I was really suprized and happy to see the patches applied to the 
> ast-optimizer-branch from Sebastian Pop. 
> His XML dumping of call graphs is very useful. 
> Can I take this as general acceptance of XML dumping in the gcc? 

Not necessarily.  RMS still has to approve anything like this before we
move it to the release branch.  We can justify it only if the XML is in
some sense incomplete: insufficient for use in proprietary back ends.

> At least it has not been attacked or criticized on the mailling list.

That's because it's incomplete (not a complete dump of the program
structure).

> Also the dump-tree-dot module dumps into a format for the non-free
> software dot, a part of graphviz. I take this is an accepted practice
> of dumping tree structures for explict usage by non-free software? 

Again, no.  RMS has explicitly objected to the graphviz support, so it
probably won't be released.  However, the situation is more complicated
than you suggest: the (free software) Boost graph library supports
graphviz reading and writing, as do other free programs.  But let's not
fool ourselves: the main reason people want graphviz output is to see the
graph visually, and the way they do that is with the non-free program.  So
we might not be able to convince RMS to let us release that.

> Or is the contents of the CVS not an indication of policy at all, 
> with the policy makers not enforcing them, and the cvs commiters not
> asking for permission?

Especially on side branches, you should assume that anything there is
experimental and not necessarily accepted for release.  Non-acceptance
might be based on technical reasons or policy reasons.