linux_dsm_epyc7002/drivers/acpi/nfit
Gustavo A. R. Silva 4b56640608 ACPI: NFIT: 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>
Link: https://lore.kernel.org/r/20200319195046.GA452@embeddedor.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2020-03-25 17:08:42 -07:00
..
core.c libnvdimm: Move nvdimm_bus_attribute_group to device_type 2019-11-19 09:52:12 -08:00
intel.c libnvdimm/security: Introduce a 'frozen' attribute 2019-08-29 13:49:13 -07:00
intel.h acpi/nfit, libnvdimm: Introduce nvdimm_security_ops 2018-12-13 17:54:13 -08:00
Kconfig acpi/nfit: Add support for Intel DSM 1.8 commands 2018-12-04 10:31:11 -08:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mce.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 295 2019-06-05 17:36:38 +02:00
nfit.h ACPI: NFIT: Replace zero-length array with flexible-array member 2020-03-25 17:08:42 -07:00