I just tried to cross-build hpcmips on i386.  For reasons not really
relevant here, I happened to have . early in my PATH when I did this.
The build broke

#      link  mv/mv
/home/mouse/hpcmips/OBJDIR/tooldir.NetBSD-3.1-i386/bin/mipsel--netbsd-gcc -Wl,-nostdlib     -o mv  -Wl,-dynamic-linker=/libexec/ld.elf_so -Wl,-rpath-link,/home/mouse/hpcmips/DESTDIR/lib:/home/mouse/hpcmips/DESTDIR/usr/lib  -R/lib  -L/home/mouse/hpcmips/DESTDIR/lib  -B/home/mouse/hpcmips/DESTDIR/usr/lib/ -B/home/mouse/hpcmips/DESTDIR/usr/lib/   mv.o   -L/home/mouse/hpcmips/DESTDIR/usr/lib -L/home/mouse/hpcmips/DESTDIR/usr/lib
#    format  mv/mv.cat1
PATH=/home/mouse/hpcmips/OBJDIR/tooldir.NetBSD-3.1-i386/lib/groff:${PATH} /home/mouse/hpcmips/OBJDIR/tooldir.NetBSD-3.1-i386/bin/nbnroff -mandoc /usr/src/bin/mv/mv.1   > mv.cat1.tmp && mv mv.cat1.tmp mv.cat1
mv: 1: Syntax error: "(" unexpected
[cascade of failures up to the top level, snipped]

Yes, having . in the path is arguably a bad idea in general, and I
wouldn't be too surprised if a build refused to run under those
circumstances.  But this is definitely not a correct way for it to
fail, it seems to me.

Worth a PR?

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