@@ -144,32 +144,32 @@ struct nfit_spa {
unsigned long ars_state;
u32 clear_err_unit;
u32 max_ars;
- struct acpi_nfit_system_address spa[0];
+ struct acpi_nfit_system_address spa[];
};
struct nfit_dcr {
struct list_head list;
- struct acpi_nfit_control_region dcr[0];
+ struct acpi_nfit_control_region dcr[];
};
struct nfit_bdw {
struct list_head list;
- struct acpi_nfit_data_region bdw[0];
+ struct acpi_nfit_data_region bdw[];
};
struct nfit_idt {
struct list_head list;
- struct acpi_nfit_interleave idt[0];
+ struct acpi_nfit_interleave idt[];
};
struct nfit_flush {
struct list_head list;
- struct acpi_nfit_flush_address flush[0];
+ struct acpi_nfit_flush_address flush[];
};
struct nfit_memdev {
struct list_head list;
- struct acpi_nfit_memory_map memdev[0];
+ struct acpi_nfit_memory_map memdev[];
};
enum nfit_mem_flags {
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> --- drivers/acpi/nfit/nfit.h | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)