mirror of https://gitee.com/openkylin/linux.git
02bddf21c3
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]
sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.
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
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| .. | ||
| book3s32 | ||
| book3s64 | ||
| kasan | ||
| nohash | ||
| ptdump | ||
| Makefile | ||
| copro_fault.c | ||
| dma-noncoherent.c | ||
| drmem.c | ||
| fault.c | ||
| highmem.c | ||
| hugetlbpage.c | ||
| init-common.c | ||
| init_32.c | ||
| init_64.c | ||
| ioremap.c | ||
| ioremap_32.c | ||
| ioremap_64.c | ||
| mem.c | ||
| mmap.c | ||
| mmu_context.c | ||
| mmu_decl.h | ||
| numa.c | ||
| pgtable-frag.c | ||
| pgtable.c | ||
| pgtable_32.c | ||
| pgtable_64.c | ||
| slice.c | ||