Use portable tr syntax.

diff --git a/config.guess b/config.guess
index 35bb308..5e0068d 100755 (executable)
--- a/config.guess
+++ b/config.guess
@@ -322,7 +322,7 @@ EOF
        exit 0 ;;
     CRAY*[A-Z]90:*:*:*)
        echo ${UNAME_MACHINE}-cray-unicos${UNAME_RELEASE} \
-       | sed -e 's/CRAY.*\([A-Z]90\)/\1/' | tr A-Z a-z
+       | sed -e 's/CRAY.*\([A-Z]90\)/\1/' | tr '[A-Z]' '[a-z]'
        exit 0 ;;
     CRAY-2:*:*:*)
        echo cray2-cray-unicos