https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109818
--- Comment #3 from Janez Zemva <janezz55 at gmail dot com> --- I am the "maintainer" of this dosbox-gcc aur (mostly I just borrow from other builds). I have told the DJGPP community about this issue 2 times and they shrugged it off, since they mostly compile .c source files. I don't think most of them even know of these 2 configure options you mentioned and I failed to spot them when I looked into configure. My impression is that configure itself figured it needed this obsolete header and the build also finishes just fine without having to specify anything extra, just that std::trunc() is later unavailable (which doesn't bother anyone since they are mostly C users). I experimented with various env and configure options, but found nothing that worked, so I resolved to just hack <cmath>. Now I'll take another look.
