diff options
| author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-03-20 00:45:31 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2020-03-22 14:52:52 +0300 |
| commit | 33ad1e5db06c94126352f785e9f0a08e867cb94c (patch) | |
| tree | 9c4945fe5fd07992c86eb24b376d442330ed22f4 /drivers/irqchip | |
| parent | b2e1cbfd2d4af6f0797ed259de5f48e7dde60014 (diff) | |
| download | linux-33ad1e5db06c94126352f785e9f0a08e867cb94c.tar.xz | |
irqchip/qcom-irq-combiner: 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: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200319214531.GA21326@embeddedor.com
Diffstat (limited to 'drivers/irqchip')
| -rw-r--r-- | drivers/irqchip/qcom-irq-combiner.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/irqchip/qcom-irq-combiner.c b/drivers/irqchip/qcom-irq-combiner.c index abfe59284ff2..aa54bfcb0433 100644 --- a/drivers/irqchip/qcom-irq-combiner.c +++ b/drivers/irqchip/qcom-irq-combiner.c @@ -33,7 +33,7 @@ struct combiner { int parent_irq; u32 nirqs; u32 nregs; - struct combiner_reg regs[0]; + struct combiner_reg regs[]; }; static inline int irq_nr(u32 reg, u32 bit) |