oic; fix compiler warning when using isalpha() with newlib.
@@ -34,7 +34,7 @@ oc_str_to_uuid(const char *str, oc_uuid_t *uuid)
for (i = 0; i < strlen(str); i++) {
if (str[i] == '-')
continue;
- else if (isalpha(str[i])) {
+ else if (isalpha((int)str[i])) {
switch (str[i]) {
case 65:
case 97:
