diff options
authorGustavo A. R. Silva <>2020-02-21 10:00:05 -0600
committerBartlomiej Zolnierkiewicz <>2020-03-02 16:32:17 +0100
commit451787d3e2ac3a25abae91792b7154ee533b65c6 (patch)
parent9dff9a3666f15f4c76d9ddfa52744a1e86fd0ff6 (diff)
video: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] This issue was found with the help of Coccinelle. [1] [2] [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <> Signed-off-by: Bartlomiej Zolnierkiewicz <> Link:
3 files changed, 3 insertions, 3 deletions
diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
index 335d4983dc52..167585a889d3 100644
--- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
+++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
@@ -1406,7 +1406,7 @@ struct mmphw_ctrl {
int path_num;
- struct mmphw_path_plat path_plats[0];
+ struct mmphw_path_plat path_plats[];
static inline int overlay_is_vid(struct mmp_overlay *overlay)
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index 1a0bd78f9345..12fa1050f3eb 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -89,7 +89,7 @@ struct ssd1307fb_par {
struct ssd1307fb_array {
u8 type;
- u8 data[0];
+ u8 data[];
static const struct fb_fix_screeninfo ssd1307fb_fix = {
diff --git a/include/video/mmp_disp.h b/include/video/mmp_disp.h
index 1f9bc133e230..77252cb46361 100644
--- a/include/video/mmp_disp.h
+++ b/include/video/mmp_disp.h
@@ -231,7 +231,7 @@ struct mmp_path {
/* layers */
int overlay_num;
- struct mmp_overlay overlays[0];
+ struct mmp_overlay overlays[];
extern struct mmp_path *mmp_get_path(const char *name);