summaryrefslogtreecommitdiff
path: root/Kbuild
diff options
context:
space:
mode:
authorGustavo A. R. Silva <gustavo@embeddedor.com>2020-04-02 07:03:52 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-02 19:35:25 +0300
commitfa803cf8f39feba691732a78e47797c5dc388ba2 (patch)
treef29cc41d16eefa6b9c9a730c2e27ad2251cf3b8b /Kbuild
parent3c9210d45d50edd13aca45131522211b93c7812d (diff)
downloadlinux-fa803cf8f39feba691732a78e47797c5dc388ba2.tar.xz
ocfs2: cluster: 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://urldefense.com/v3/__https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html__;!!GqivPVa7Brio!NzMr-YRl2zy-K3lwLVVatz7x0uD2z7-ykQag4GrGigxmfWU8TWzDy6xrkTiW3hYl00czlw$ [2] https://urldefense.com/v3/__https://github.com/KSPP/linux/issues/21__;!!GqivPVa7Brio!NzMr-YRl2zy-K3lwLVVatz7x0uD2z7-ykQag4GrGigxmfWU8TWzDy6xrkTiW3hYHG1nAnw$ [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Link: http://lkml.kernel.org/r/20200309201907.GA8005@embeddedor Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Kbuild')
0 files changed, 0 insertions, 0 deletions