From 9a93c6686f56086fe5280a85513041bbfebf41d0 Mon Sep 17 00:00:00 2001 From: Jeff King Date: Tue, 29 Dec 2015 01:35:46 -0500 Subject: [PATCH] avoid shifting signed integers 31 bits We sometimes use 32-bit unsigned integers as bit-fields. It's fine to access the MSB, because it's unsigned. However, doing so as "1 << 31" is wrong, because the constant "1" is a signed int, and we shift into the sign bit, causing undefined behavior. We can fix this by using "1U" as the constant. Signed-off-by: Jeff King Signed-off-by: Junio C Hamano --- builtin/receive-pack.c | 2 +- cache.h | 2 +- diff.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index e6b93d0264..e35ed40437 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -1597,7 +1597,7 @@ static void prepare_shallow_update(struct command *commands, continue; si->need_reachability_test[i]++; for (k = 0; k < 32; k++) - if (si->used_shallow[i][j] & (1 << k)) + if (si->used_shallow[i][j] & (1U << k)) si->shallow_ref[j * 32 + k]++; } diff --git a/cache.h b/cache.h index 6f53962bf2..908884318c 100644 --- a/cache.h +++ b/cache.h @@ -214,7 +214,7 @@ struct cache_entry { #define CE_INTENT_TO_ADD (1 << 29) #define CE_SKIP_WORKTREE (1 << 30) /* CE_EXTENDED2 is for future extension */ -#define CE_EXTENDED2 (1 << 31) +#define CE_EXTENDED2 (1U << 31) #define CE_EXTENDED_FLAGS (CE_INTENT_TO_ADD | CE_SKIP_WORKTREE) diff --git a/diff.h b/diff.h index f7208ad103..893f446517 100644 --- a/diff.h +++ b/diff.h @@ -91,7 +91,7 @@ typedef struct strbuf *(*diff_prefix_fn_t)(struct diff_options *opt, void *data) #define DIFF_OPT_DIRSTAT_BY_LINE (1 << 28) #define DIFF_OPT_FUNCCONTEXT (1 << 29) #define DIFF_OPT_PICKAXE_IGNORE_CASE (1 << 30) -#define DIFF_OPT_DEFAULT_FOLLOW_RENAMES (1 << 31) +#define DIFF_OPT_DEFAULT_FOLLOW_RENAMES (1U << 31) #define DIFF_OPT_TST(opts, flag) ((opts)->flags & DIFF_OPT_##flag) #define DIFF_OPT_TOUCHED(opts, flag) ((opts)->touched_flags & DIFF_OPT_##flag) -- 2.11.4.GIT