Fix "past the beginning of string" test.

diff --git a/gpsbabel/mkshort.c b/gpsbabel/mkshort.c
index 1efcb7812b3c2bb0f1af8c0a9ad349d05390a66a..8edef7683a41813265cbf5e26c55b61f05c876ee 100644 (file)
--- a/gpsbabel/mkshort.c
+++ b/gpsbabel/mkshort.c
@@ -387,7 +387,7 @@ mkshort(void *h, const char *istring)
         * Walk in the Woods 2.
         */
        np = ostring + strlen(ostring);
-       while (*np && isdigit(*(np-1) )) {
+       while (*(np-1) && isdigit(*(np-1) )) {
                np--;
        }
        if (np) {