On 5/16/22 06:31, Greg KH wrote:
On Mon, May 16, 2022 at 06:10:23AM -0700, Guenter Roeck wrote:
On Mon, Feb 28, 2022 at 11:27:43AM +0100, Arnd Bergmann wrote:
From: Arnd Bergmann <arnd@xxxxxxxx>
During a patch discussion, Linus brought up the option of changing
the C standard version from gnu89 to gnu99, which allows using variable
declaration inside of a for() loop. While the C99, C11 and later standards
introduce many other features, most of these are already available in
gnu89 as GNU extensions as well.
The downside is that backporting affected patches to older kernel branches
now fails with error messages such as
mm/kfence/core.c: In function ‘kfence_init_pool’:
mm/kfence/core.c:595:2: error: ‘for’ loop initial declarations are only allowed in C99 or C11 mode
Just something to keep in mind when writing patches.
I just ran across this very issue on this commit. It's an easy fixup
for 5.17.y to make this work, so I did that in my tree. If this gets to
be too much, we might need to reconsider adding c11 to older stable
kernels.
I think I'll do just that for ChromeOS; I don't want to have to deal
with the backports, and we are using recent compilers anyway.
Guenter
