It may happen when two drivers share one winsys.
])
dnl Sort the dirs alphabetically
-GALLIUM_TARGET_DIRS=`echo $GALLIUM_TARGET_DIRS|tr " " "\n"|sort|tr "\n" " "`
-GALLIUM_WINSYS_DIRS=`echo $GALLIUM_WINSYS_DIRS|tr " " "\n"|sort|tr "\n" " "`
-GALLIUM_DRIVERS_DIRS=`echo $GALLIUM_DRIVERS_DIRS|tr " " "\n"|sort|tr "\n" " "`
-GALLIUM_STATE_TRACKERS_DIRS=`echo $GALLIUM_STATE_TRACKERS_DIRS|tr " " "\n"|sort|tr "\n" " "`
+GALLIUM_TARGET_DIRS=`echo $GALLIUM_TARGET_DIRS|tr " " "\n"|sort -u|tr "\n" " "`
+GALLIUM_WINSYS_DIRS=`echo $GALLIUM_WINSYS_DIRS|tr " " "\n"|sort -u|tr "\n" " "`
+GALLIUM_DRIVERS_DIRS=`echo $GALLIUM_DRIVERS_DIRS|tr " " "\n"|sort -u|tr "\n" " "`
+GALLIUM_STATE_TRACKERS_DIRS=`echo $GALLIUM_STATE_TRACKERS_DIRS|tr " " "\n"|sort -u|tr "\n" " "`
AC_OUTPUT