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")
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| @@ -326,7 +326,7 @@ struct sctp_cookie { · 325 unmodified lines | ||
| 326 | 326 | * the association TCB is re-constructed from the cookie. |
| 327 | 327 | */ |
| 328 | 328 | __u32 raw_addr_list_len; |
| 329 | − struct sctp_init_chunk peer_init[0]; | |
| 329 | + struct sctp_init_chunk peer_init[]; | |
| 330 | 330 | }; |
| 331 | 331 | |
| 332 | 332 | |