[RFC] Replicate src dir in build dir

[Tom Tromey]

>>>>> "Yao" == Yao Qi <qiyaoltc@gmail.com> writes:

Yao> Right, I should add $(basename ) back, like the patch
Yao> below.

Yeah.  Actually I wanted this to work so I sent a patch recently, which
is in now.

Yao> If I understand you correctly, depcomp has already
Yao> taken care of it.  See my reply to Simon's review.
Yao> https://sourceware.org/ml/gdb-patches/2017-09/msg00489.html

Yep, that's right; though it turned out that this code didn't work for
other reasons (nothing to do with your change); I fixed that as well.

Tom