[arch-general] PKGBUILD problem Can't exec "aclocal":

I wonder if anyone can help me trace how to fix this error message: Can't exec "aclocal": No such file or directory at /usr/share/autoconf/Autom4te/FileUtils.pm line 326. autoreconf: failed to run aclocal: No such file or directory which seems to be holding up one of my PKGBUILDs which does in fact compile on my laptop, but now won't on a new machine, so I'm obviously missing something. Thanks.