-# Separate what the user gave into CPU-COMPANY and OS (if any).
-basic_machine=`echo $1 | sed 's/-[^-]*$//'`
-if [ $basic_machine != $1 ]
-then os=`echo $1 | sed 's/.*-/-/'`
-else os=; fi
+# Separate what the user gave into CPU-COMPANY and OS or KERNEL-OS (if any).
+# Here we must recognize all the valid KERNEL-OS combinations.
+maybe_os=`echo $1 | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\2/'`
+case $maybe_os in
+ linux-gnu*)
+ os=-$maybe_os
+ basic_machine=`echo $1 | sed 's/^\(.*\)-\([^-]*-[^-]*\)$/\1/'`
+ ;;
+ *)
+ basic_machine=`echo $1 | sed 's/-[^-]*$//'`
+ if [ $basic_machine != $1 ]
+ then os=`echo $1 | sed 's/.*-/-/'`
+ else os=; fi
+ ;;
+esac