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Subject[PATCH] USB: serial: ti_usb_3410_5052: 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
inadvertenly introduced[3] to the codebase from now on.

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/usb/serial/ti_usb_3410_5052.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/serial/ti_usb_3410_5052.c b/drivers/usb/serial/ti_usb_3410_5052.c
index dd0ad67aa71e..db3ab25d9228 100644
--- a/drivers/usb/serial/ti_usb_3410_5052.c
+++ b/drivers/usb/serial/ti_usb_3410_5052.c
@@ -219,7 +219,7 @@ struct ti_write_data_bytes {
u8 bDataCounter;
__be16 wBaseAddrHi;
__be16 wBaseAddrLo;
- u8 bData[0];
+ u8 bData[];
} __packed;

struct ti_read_data_request {
@@ -234,7 +234,7 @@ struct ti_read_data_bytes {
__u8 bCmdCode;
__u8 bModuleId;
__u8 bErrorCode;
- __u8 bData[0];
+ __u8 bData[];
} __packed;

/* Interrupt struct */
--
2.25.0
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