Re: mt-mep using EXTRA_TARGET_HOST_ALL_MODULES?

[Paolo Bonzini <bonzini at gnu dot org>]

On 03/25/2011 11:59 AM, Joseph S. Myers wrote:
> > * Maybe turn it into a build tool, and it may even make sense:
> > dejagnu
>
> dejagnu and expect used to have copies in the src tree but they were
> removed a long time ago, so I think of the rules for them both as a
> legacy (and I think those two go together).  If they are removed, gcc
> subdirectory code supporting in-tree runtest and expect could be removed
> as well (it's quite possible other subdirectories in the gcc and src trees
> also have support for various components in-tree, that could be removed).

The subdirectory code supporting in-tree runtest should be moved to the 
toplevel anyway.  Adding in-tree expect as a build module makes little 
sense, though.  It has a further dependency on tcl so it's not like your 
reaching the bottom of the chain.

> > * Also present as build modules, host module makes little sense though:
> > bison byacc flex m4 texinfo
>
> texinfo used to have a copy in the GCC tree but was removed a long time
> ago; the src tree deliberately only has a copy of texinfo.tex in the
> toplevel texinfo directory.

This doesn't matter.  You could in principle drop an out-of-tree texinfo 
directory and use its makeinfo to build GCC.

> So I think of the rules for it as a legacy.

Actually support for in-tree build tools is quite recent (2005-ish).

> I don't see m4 as useful as a build tool (rather, it's used by autoconf),

It's used by libgfortran too.

> nor the use of having both byacc and bison, and while build tools bison
> and flex could be used I doubt the real utility of building them in tree.

I agree that byacc can be dropped.  I just wouldn't drop 
flex/bison/m4/texinfo right now.  I would like to separate removal of 
obsolete Cygnus-tree remnants, from removal of features that we just 
don't care about anymore.  Building bison as a host module is the 
former; building bison as a build module is the latter.

Paolo