[bug-gettext] msgmerge --for-msgfmt

[Daiki Ueno]

Hello Bruno,

I got a report saying that the .pot-update rule doesn't work if the
project is configured with the gettext infrastructure from 0.20.1:
https://lists.freedesktop.org/archives/p11-glue/2019-May/000700.html

Apparently, if the input .po file contains no translation (i.e., all
msgstr's are ""), msgmerge --for-msgfmt doesn't produce any output and
thus the later msgfmt call fails.

I suspect that this might be an intended behavior, because we probably
should remove the .po file then.  Having said that, wouldn't it be nice
to print more appropriate message on msgmerge --for-msgfmt call?

Regards,
-- 
Daiki Ueno