apparently some distros use this form, and it seems to be supported in
the gcc build system.
mips*) ARCH=mips ;;
microblaze*) ARCH=microblaze ;;
or1k*) ARCH=or1k ;;
-powerpc64*) ARCH=powerpc64 ;;
-powerpc*) ARCH=powerpc ;;
+powerpc64*|ppc64*) ARCH=powerpc64 ;;
+powerpc*|ppc*) ARCH=powerpc ;;
sh[1-9bel-]*|sh|superh*) ARCH=sh ;;
s390x*) ARCH=s390x ;;
unknown) fail "$0: unable to detect target arch; try $0 --target=..." ;;