treewide: uapi: Replace zero-length arrays with flexible-array members

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a stru

treewide: uapi: Replace zero-length arrays with flexible-array members

There is a regular need in the kernel to provide a way to declare
having a dynamically sized set of trailing elements in a structure.
Kernel code should always use “flexible array members”[1] for these
cases. The older style of one-element or zero-length arrays should
no longer be used[2].

This code was transformed with the help of Coccinelle:
(linux-5.19-rc2$ spatch --jobs $(getconf _NPROCESSORS_ONLN) --sp-file script.cocci --include-headers --dir . > output.patch)

@@
identifier S, member, array;
type T1, T2;
@@

struct S {
...
T1 member;
T2 array[
- 0
];
};

-fstrict-flex-arrays=3 is coming and we need to land these changes
to prevent issues like these in the short future:

../fs/minix/dir.c:337:3: warning: 'strcpy' will always overflow; destination buffer has size 0,
but the source string has length 2 (including NUL byte) [-Wfortify-source]
strcpy(de3->name, ".");
^

Since these are all [0] to [] changes, the risk to UAPI is nearly zero. If
this breaks anything, we can use a union with a new member name.

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://www.kernel.org/doc/html/v5.16/process/deprecated.html#zero-length-and-one-element-arrays

Link: https://github.com/KSPP/linux/issues/78
Build-tested-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/lkml/62b675ec.wKX6AOZ6cbE71vtF%[email protected]/
Acked-by: Dan Williams <[email protected]> # For ndctl.h
Signed-off-by: Gustavo A. R. Silva <[email protected]>

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jffs2: Remove C++ style comments from uapi header

Linux kernel tolerates C++ style comments these days. Actually, the
SPDX License tags for .c files start with //.

On the other hand, uapi headers a

jffs2: Remove C++ style comments from uapi header

Linux kernel tolerates C++ style comments these days. Actually, the
SPDX License tags for .c files start with //.

On the other hand, uapi headers are written in more strict C, where
the C++ comment style is forbidden.

I simply dropped these lines instead of fixing the comment style.

This code has been always commented out since it was added around
Linux 2.4.9 (i.e. commented out for more than 17 years).

'Maybe later...' will never happen.

Signed-off-by: Masahiro Yamada <[email protected]>
Acked-by: Richard Weinberger <[email protected]>
Signed-off-by: Richard Weinberger <[email protected]>

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UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Michae

UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <[email protected]>
Acked-by: Arnd Bergmann <[email protected]>
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Michael Kerrisk <[email protected]>
Acked-by: Paul E. McKenney <[email protected]>
Acked-by: Dave Jones <[email protected]>

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