cleanup: fix possible overflow errors in binary search

A common mistake when writing binary search is to allow possible
integer overflow by using the simple average:

	mid = (min + max) / 2;

Instead, use the overflow-safe version:

	mid = min + (max - min) / 2;

This translation is safe since the operation occurs inside a loop
conditioned on "min < max". The included changes were found using
the following git grep:

	git grep '/ *2;' '*.c'

Making this cleanup will prevent future review friction when a new
binary search is contructed based on existing code.

Signed-off-by: Derrick Stolee <dstolee@microsoft.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/compat/regex/regexec.c b/compat/regex/regexec.c
index 0a745d9c3b..6f2b48a78b 100644
--- a/compat/regex/regexec.c
+++ b/compat/regex/regexec.c
@@ -4284,7 +4284,7 @@ search_cur_bkref_entry (const re_match_context_t *mctx, int str_idx)
   last = right = mctx->nbkref_ents;
   for (left = 0; left < right;)
     {
-      mid = (left + right) / 2;
+      mid = left + (right - left) / 2;
       if (mctx->bkref_ents[mid].str_idx < str_idx)
 	left = mid + 1;
       else