path: root/drivers/rpmsg
diff options
authorGustavo A. R. Silva <>2020-05-07 14:19:48 -0500
committerBjorn Andersson <>2020-05-12 15:00:48 -0700
commit4f05fc33bebdc7d69259c412dd21d09751827dbd (patch)
treea35f9bc30082c963b1539c1e0795e4182d0df1ca /drivers/rpmsg
parent075894d45656fe9aeced4f34ef692b52791d78dc (diff)
rpmsg: Replace zero-length array with flexible-array
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] [2] [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva <> Link: Signed-off-by: Bjorn Andersson <>
Diffstat (limited to 'drivers/rpmsg')
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 376ebbf880d6..07d4f3374098 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -89,7 +89,7 @@ struct rpmsg_hdr {
u32 reserved;
u16 len;
u16 flags;
- u8 data[0];
+ u8 data[];
} __packed;