In shorten_unambiguous_ref, we build and cache a reverse-map of the rev-parse rules like this: static char **scanf_fmts; static int nr_rules; if (!nr_rules) { for (; ref_rev_parse_rules[nr_rules]; nr_rules++) ... generate scanf_fmts ... } where ref_rev_parse_rules is terminated with a NULL pointer. Compiling with "gcc -O2 -Wall" does not cause any problems, but compiling with "-O3 -Wall" generates: $ make CFLAGS='-O3 -Wall' refs.o refs.c: In function ‘shorten_unambiguous_ref’: refs.c:3379:29: warning: array subscript is above array bounds [-Warray-bounds] for (; ref_rev_parse_rules[nr_rules]; nr_rules++) Curiously, we can silence this by explicitly nr_rules to 0 in the beginning of the loop, even though the compiler should be able to tell that we follow this code path only when nr_rules is already 0. Signed-off-by: Jeff King <peff@xxxxxxxx> --- This is a repost of: http://article.gmane.org/gmane.comp.version-control.git/235703 which contains a little more cover-letter discussion. refs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/refs.c b/refs.c index 3710748..0c0e963 100644 --- a/refs.c +++ b/refs.c @@ -3376,7 +3376,7 @@ char *shorten_unambiguous_ref(const char *refname, int strict) size_t total_len = 0; /* the rule list is NULL terminated, count them first */ - for (; ref_rev_parse_rules[nr_rules]; nr_rules++) + for (nr_rules = 0; ref_rev_parse_rules[nr_rules]; nr_rules++) /* no +1 because strlen("%s") < strlen("%.*s") */ total_len += strlen(ref_rev_parse_rules[nr_rules]); -- 1.8.4.1.898.g8bf8a41.dirty -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html