diff options
author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-03-20 18:25:15 -0500 |
---|---|---|
committer | Mark Brown <broonie@kernel.org> | 2020-03-23 18:37:07 +0000 |
commit | 6960b0332c75efbade990f047da073e5f3ef1af4 (patch) | |
tree | eba2d716b239fa2cf3189f635330c029c5ef3a26 /drivers/spi | |
parent | 2d4ccc2ac61b1a407a1c75633a3bf2f878ff44b5 (diff) |
spi: spi-fsl-lpspi: 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/20200320232515.GA24800@embeddedor.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-fsl-lpspi.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c index 298329b781d2..8b41b70f6f5c 100644 --- a/drivers/spi/spi-fsl-lpspi.c +++ b/drivers/spi/spi-fsl-lpspi.c @@ -123,7 +123,7 @@ struct fsl_lpspi_data { struct completion dma_rx_completion; struct completion dma_tx_completion; - int chipselect[0]; + int chipselect[]; }; static const struct of_device_id fsl_lpspi_dt_ids[] = { |