linux_dsm_epyc7002/include
Gustavo A. R. Silva b90feaff2a net: sched: 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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-29 21:27:02 -08:00
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acpi
asm-generic
clocksource
crypto
drm
dt-bindings
keys
kunit
kvm
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-02-29 15:53:35 -08:00
math-emu
media
misc
net net: sched: Replace zero-length array with flexible-array member 2020-02-29 21:27:02 -08:00
pcmcia
ras
rdma
scsi
soc
sound
target
trace
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next 2020-02-29 15:53:35 -08:00
vdso
video
xen