diff.h: fix index used to loop through unsigned integer

The `struct diff_flags` structure is essentially an array of flags, all
of which have the same type. We can thus use `sizeof()` to iterate
through all of the flags, which we do in `diff_flags_or()`. But while
the statement returns an unsigned integer, we used a signed integer to
iterate through the flags, which generates a warning.

Fix this by using `size_t` for the index instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/diff.h b/diff.h
index 5c8de79535..6e6007c17b 100644
--- a/diff.h
+++ b/diff.h
@@ -205,9 +205,8 @@ static inline void diff_flags_or(struct diff_flags *a,
 {
 	char *tmp_a = (char *)a;
 	const char *tmp_b = (const char *)b;
-	int i;
 
-	for (i = 0; i < sizeof(struct diff_flags); i++)
+	for (size_t i = 0; i < sizeof(struct diff_flags); i++)
 		tmp_a[i] |= tmp_b[i];
 }