With `confess' after `exec', perl complains
Statement unlikely to be reached at /usr/share/perl5/Debian/Dgit.pm line 770.
(Maybe you meant system() when you said exec()?)
The error message's suggestion is not right here - what is wrong is
that confess is not really appropriate in the child in this way.
Replace it with die, using a better error string.
Signed-off-by: Ian Jackson <email@example.com>