[Bug ada/55243] STAMP variable is not defined in t-avr

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55243

--- Comment #20 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2012-12-10 22:57:41 UTC ---
(In reply to comment #19)
>> It works with read-only sources, provided everything is consistent.  Or are
>> you saying that a t-snip must not use $(STAMP)?
> 
> I'm saying that the build process should never touch the source tree.

Isn't ./gcc/doc/md.texi both in the repo and generated (from
./gcc/doc/md.texi.in)?  And, if parts of the docs are changed you will we
nagged to verify GFDL and to copy the new, auto-generated parts in place?

>> Actually, the PR boils down to the fact the STAMP is not defined, I am not
>> sure if the compiler is supposed to build without STAMP.
> 
> Probably not, but what I'm trying to understand is why we seem to be fiddling
> with the source tree when building the gnattools.

As far as gnattools are concerned, it makes no difference whether the
auto-generated files are stamped and written to $build or stamped and written
to $source.

I agree that the $source vs. $build matter should be cleaned up.

However, that won't help with this PR because the rules and the dependencies
and the needed tools will remain the same.