jimsh: Fix crash with "throw 8"

Off by one for length of the return code name array.
Found with afl-fuzz.

Signed-off-by: Steve Bennett <steveb@workware.net.au>

1 files changed, 1 insertions, 1 deletions

diff --git a/jim.c b/jim.c
index 6e34d48..691f635 100644
--- a/jim.c
+++ b/jim.c
@@ -7513,7 +7513,7 @@ static const char * const jimReturnCodes[] = {
     NULL
 };
 
-#define jimReturnCodesSize (sizeof(jimReturnCodes)/sizeof(*jimReturnCodes))
+#define jimReturnCodesSize (sizeof(jimReturnCodes)/sizeof(*jimReturnCodes) - 1)
 
 static const Jim_ObjType returnCodeObjType = {
     "return-code",