nmh builds mostly OK under it, and passes 'make check'. However,
there's a whole mess of new warnings, which all root-cause to the
fact that gcc8 apparently does sanity checking on whether the code
has bounds-checked the length parameter of snprintf() and friends
before using it, and special-case notification when it's obvious that
the destination won't get null-terminated.
I'm ... a little confused. Is the "right" way to deal with that by
adr[sizeof(adr) - 1] = '\0';
strncpy(adr, ap->text, sizeof(adr) - 1);
Or something else? A quick Google suggests most people "fix" this by
adding -Wno-stringop-truncation to the build options.