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| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-02-13 03:37:03 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2020-02-13 17:45:35 +0300 |
| commit | 57a8cc725622185576dcd3df718e91fcda1ef5dd (patch) | |
| tree | c68e3d80ca796a4ab7b9633bed4dee5c9e5c52f9 /drivers/dma/bcm-sba-raid.c | |
| parent | ff095986e6b449bc095b018388519f1e413a7fa8 (diff) | |
| download | linux-57a8cc725622185576dcd3df718e91fcda1ef5dd.tar.xz | |
dmaengine: bcm-sba-raid: 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>
Link: https://lore.kernel.org/r/20200213003703.GA4177@embeddedor.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Diffstat (limited to 'drivers/dma/bcm-sba-raid.c')
| -rw-r--r-- | drivers/dma/bcm-sba-raid.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/dma/bcm-sba-raid.c b/drivers/dma/bcm-sba-raid.c index 275e90fa829d..64239da02e74 100644 --- a/drivers/dma/bcm-sba-raid.c +++ b/drivers/dma/bcm-sba-raid.c @@ -120,7 +120,7 @@ struct sba_request { struct brcm_message msg; struct dma_async_tx_descriptor tx; /* SBA commands */ - struct brcm_sba_command cmds[0]; + struct brcm_sba_command cmds[]; }; enum sba_version { |