diff mbox

[FFmpeg-devel] libavcodec/iff: Use unsigned to avoid undefined behaviour

Message ID 20190802202916.11594-1-andreas.rheinhardt@gmail.com
State Accepted
Commit f12e662a3d3f489eec887b5f2ab20a550caed9cf
Headers show

Commit Message

Andreas Rheinhardt Aug. 2, 2019, 8:29 p.m. UTC 
The initialization of the uint32_t plane32_lut matrix uses left shifts
of the form 1 << plane; plane can be as big as 31 which means that this
is undefined behaviour as 1 will be simply an int. So make it unsigned
to avoid this.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
---
 libavcodec/iff.c | 34 +++++++++++++++++-----------------
 1 file changed, 17 insertions(+), 17 deletions(-)

Comments

Paul B Mahol Aug. 5, 2019, 1:43 p.m. UTC | #1 
LGTM
Michael Niedermayer Aug. 5, 2019, 3:12 p.m. UTC | #2 
On Mon, Aug 05, 2019 at 03:43:23PM +0200, Paul B Mahol wrote:
> LGTM

will apply

thx

[...]
diff mbox

Patch

diff --git a/libavcodec/iff.c b/libavcodec/iff.c
index 7f1c589d7c..fc7bfad731 100644
--- a/libavcodec/iff.c
+++ b/libavcodec/iff.c
@@ -111,23 +111,23 @@  static const uint64_t plane8_lut[8][256] = {
     LUT8(4), LUT8(5), LUT8(6), LUT8(7),
 };
 
-#define LUT32(plane) {                                \
-             0,          0,          0,          0,   \
-             0,          0,          0, 1 << plane,   \
-             0,          0, 1 << plane,          0,   \
-             0,          0, 1 << plane, 1 << plane,   \
-             0, 1 << plane,          0,          0,   \
-             0, 1 << plane,          0, 1 << plane,   \
-             0, 1 << plane, 1 << plane,          0,   \
-             0, 1 << plane, 1 << plane, 1 << plane,   \
-    1 << plane,          0,          0,          0,   \
-    1 << plane,          0,          0, 1 << plane,   \
-    1 << plane,          0, 1 << plane,          0,   \
-    1 << plane,          0, 1 << plane, 1 << plane,   \
-    1 << plane, 1 << plane,          0,          0,   \
-    1 << plane, 1 << plane,          0, 1 << plane,   \
-    1 << plane, 1 << plane, 1 << plane,          0,   \
-    1 << plane, 1 << plane, 1 << plane, 1 << plane,   \
+#define LUT32(plane) {                                    \
+              0,           0,           0,           0,   \
+              0,           0,           0, 1U << plane,   \
+              0,           0, 1U << plane,           0,   \
+              0,           0, 1U << plane, 1U << plane,   \
+              0, 1U << plane,           0,           0,   \
+              0, 1U << plane,           0, 1U << plane,   \
+              0, 1U << plane, 1U << plane,           0,   \
+              0, 1U << plane, 1U << plane, 1U << plane,   \
+    1U << plane,           0,           0,           0,   \
+    1U << plane,           0,           0, 1U << plane,   \
+    1U << plane,           0, 1U << plane,           0,   \
+    1U << plane,           0, 1U << plane, 1U << plane,   \
+    1U << plane, 1U << plane,           0,           0,   \
+    1U << plane, 1U << plane,           0, 1U << plane,   \
+    1U << plane, 1U << plane, 1U << plane,           0,   \
+    1U << plane, 1U << plane, 1U << plane, 1U << plane,   \
 }
 
 // 32 planes * 4-bit mask * 4 lookup tables each