https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89020
--- Comment #11 from Jerry DeLisle <jvdelisle at gcc dot gnu.org> --- (In reply to Dominique d'Humieres from comment #10) > It seems that the GCC policy is "s/can not/cannot/g". Thanks Dominique, I will fix it. BTW I set up Ubuntu 18 in Virtualbox 6 on Win 10 and it does not have the problem. (Or at least as I set it up, being not too familiar with it.) Luke, you may want to just update your environmnet. Regardless I will commit the changes I proposed as obvious after regression testing. (I would not expect any issue with it.)