See https://debbugs.gnu.org/cgi/bugreport.cgi?bug=49901 for an
explanation. It's partially the macro itself that is buggy:
Indeed. I'm merging these bugs, although there is only a little that can
be done on the automake side, as far as I can see. --thanks, karl.
I (finally) installed this patch to quit early if the perl path has
spaces. Thanks.
As for MKDIR_P and INSTALL, I guess it is somewhere in the
prerequisite/autoconf stuff. I suppose it would be rare that they would
be found in a path with spaces while perl was not, so I think it's ok to
let that g
