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author | Philippe Mathieu-Daudé <philmd@redhat.com> | 2020-03-04 16:38:16 +0100 |
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committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-16 22:07:42 +0100 |
commit | 880a7817c1a82a93d3f83dfb25dce1f0db629c66 (patch) | |
tree | 5907b2a58f0f58a3db7893ffa8e7e5e1808960f2 /cpus-common.c | |
parent | f7795e4096d8bd1c767c5ddb450fa859ff20490e (diff) |
misc: Replace zero-length arrays with flexible array member (manual)
Description copied from Linux kernel commit from Gustavo A. R. Silva
(see [3]):
--v-- description start --v--
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], 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 unadvertenly introduced [2] to the
Linux codebase from now on.
--^-- description end --^--
Do the similar housekeeping in the QEMU codebase (which uses
C99 since commit 7be41675f7cb).
All these instances of code were found with the help of the
following command (then manual analysis, without modifying
structures only having a single flexible array member, such
QEDTable in block/qed.h):
git grep -F '[0];'
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=76497732932f
[3] https://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux.git/commit/?id=17642a2fbd2c1
Inspired-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'cpus-common.c')
0 files changed, 0 insertions, 0 deletions