path: root/kernel/gcov/fs.c
diff options
authorGustavo A. R. Silva <gustavo@embeddedor.com>2020-04-06 20:11:58 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2020-04-07 10:43:44 -0700
commit6524d79413f4ffd28480f541ef68f9ea199b2e0c (patch)
tree6b7aeb7510c06123a05e758b42e88982b828e222 /kernel/gcov/fs.c
parent7ff87182d156e90b59455aac8503da512a1c5dba (diff)
kernel/gcov/fs.c: 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 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> Cc: Peter Oberparleiter <oberpar@linux.ibm.com> Link: http://lkml.kernel.org/r/20200302224851.GA26467@embeddedor Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/gcov/fs.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c
index e5eb5ea7ea59..5e891c3c2d93 100644
--- a/kernel/gcov/fs.c
+++ b/kernel/gcov/fs.c
@@ -58,7 +58,7 @@ struct gcov_node {
struct dentry *dentry;
struct dentry **links;
int num_loaded;
- char name[0];
+ char name[];
static const char objtree[] = OBJTREE;