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Gustavo A. R. Silva fba4168ede gcov: gcc_4_7: 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 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Link: http://lkml.kernel.org/r/20200213152241.GA877@embeddedor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-04-07 10:43:44 -07:00
arch kasan: stackdepot: move filter_irq_stacks() to stackdepot.c 2020-04-07 10:43:43 -07:00
block
certs
crypto
Documentation mm/zswap: allow setting default status, compressor and allocator in Kconfig 2020-04-07 10:43:41 -07:00
drivers mm/memory_hotplug: allow to specify a default online_type 2020-04-07 10:43:41 -07:00
fs reiserfs: clean up several indentation issues 2020-04-07 10:43:44 -07:00
include linux/bits.h: add compile time sanity check of GENMASK inputs 2020-04-07 10:43:43 -07:00
init userfaultfd: wp: add WP pagetable tracking to x86 2020-04-07 10:43:39 -07:00
ipc proc: faster open/read/close with "permanent" files 2020-04-07 10:43:42 -07:00
kernel gcov: gcc_4_7: replace zero-length array with flexible-array member 2020-04-07 10:43:44 -07:00
lib lib/dynamic_debug.c: use address-of operator on section symbols 2020-04-07 10:43:43 -07:00
LICENSES
mm kasan: stackdepot: move filter_irq_stacks() to stackdepot.c 2020-04-07 10:43:43 -07:00
net 9p pull request for inclusion in 5.7 2020-04-06 08:46:59 -07:00
samples samples/hw_breakpoint: drop use of kallsyms_lookup_name() 2020-04-07 10:43:44 -07:00
scripts checkpatch: avoid warning about uninitialized_var() 2020-04-07 10:43:44 -07:00
security
sound
tools kselftest: introduce new epoll test case 2020-04-07 10:43:44 -07:00
usr
virt
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS MAINTAINERS: list the section entries in the preferred order 2020-04-07 10:43:42 -07:00
Makefile
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.