(valid_options): Don't segfault on `stty erase -'.

diff --git a/src/stty.c b/src/stty.c
index 3bbf0a6..c263747 100644 (file)
--- a/src/stty.c
+++ b/src/stty.c
@@ -680,7 +680,7 @@ valid_options (char *opt, const char *valid_opts,
 {
   char ch;
 
-  if (*opt++ != '-')
+  if (*opt++ != '-' || *opt == 0)
     return 0;
 
   while ((ch = *opt))