diff options
author | Gustavo A. R. Silva <gustavo@embeddedor.com> | 2020-04-20 13:14:01 -0500 |
---|---|---|
committer | Geert Uytterhoeven <geert@linux-m68k.org> | 2020-04-27 11:51:08 +0200 |
commit | 366b8149fbff1965f9e25bb27dd4698d654be270 (patch) | |
tree | 11514e478a076f1ca4281ae587396697e460d48b /arch/m68k/amiga | |
parent | e09a7440407900757d03aa0cd897e4fc8e7d5fac (diff) |
m68k: amiga: config: 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>
Link: https://lore.kernel.org/r/20200420181401.GA32172@embeddedor
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Diffstat (limited to 'arch/m68k/amiga')
-rw-r--r-- | arch/m68k/amiga/config.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/m68k/amiga/config.c b/arch/m68k/amiga/config.c index 777196e9c9bc..4eb911d64e8d 100644 --- a/arch/m68k/amiga/config.c +++ b/arch/m68k/amiga/config.c @@ -629,7 +629,7 @@ struct savekmsg { unsigned long magic2; /* SAVEKMSG_MAGIC2 */ unsigned long magicptr; /* address of magic1 */ unsigned long size; - char data[0]; + char data[]; }; static struct savekmsg *savekmsg; |