diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-03-20 01:42:00 +0300 |
|---|---|---|
| committer | Miquel Raynal <miquel.raynal@bootlin.com> | 2020-03-25 01:02:30 +0300 |
| commit | f1ffdbfad00a3c424cadfd307b5bb9c466638532 (patch) | |
| tree | dd5ecbef4e7eb9745bdd2a7c133c89ae6ddfa602 /drivers/mtd/maps | |
| parent | 49c64df880570034308e4a9a49c4bc95cf8cdb33 (diff) | |
| download | linux-f1ffdbfad00a3c424cadfd307b5bb9c466638532.tar.xz | |
mtd: maps: sa1100-flash: 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] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20200319224200.GA25162@embeddedor.com
Diffstat (limited to 'drivers/mtd/maps')
| -rw-r--r-- | drivers/mtd/maps/sa1100-flash.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/mtd/maps/sa1100-flash.c b/drivers/mtd/maps/sa1100-flash.c index 47602af4ee34..bb1ef650ffd2 100644 --- a/drivers/mtd/maps/sa1100-flash.c +++ b/drivers/mtd/maps/sa1100-flash.c @@ -34,7 +34,7 @@ struct sa_subdev_info { struct sa_info { struct mtd_info *mtd; int num_subdev; - struct sa_subdev_info subdev[0]; + struct sa_subdev_info subdev[]; }; static DEFINE_SPINLOCK(sa1100_vpp_lock); |