Re: Linux 6.3-rc3

From: Segher Boessenkool
Date: Mon Mar 20 2023 - 18:54:23 EST


On Mon, Mar 20, 2023 at 03:06:31PM -0700, Nathan Chancellor wrote:
> It seems like clang takes into account that the branch has no effect on
> how uninitialized err is, although it does acknowledge there may be
> control flow where err is not used uninitialized because it is not used
> at all by stating "when used here". I guess GCC does not make this
> distinction and places it under -Wmaybe-uninitialized. I could be
> totally wrong though :)

In one place we have the comment

/* Re-do the plain uninitialized variable check, as optimization may have
straightened control flow. Do this first so that we don't accidentally
get a "may be" warning when we'd have seen an "is" warning later. */

It seems we miss a similar case here?

In any case, please open a PR if you want this fixed. Thanks!


Segher