Re: [PATCH 00/10] Remove uninitialized_var() macro
From: Sedat Dilek
Date: Thu Jun 04 2020 - 03:27:13 EST
On Thu, Jun 4, 2020 at 5:33 AM Nathan Chancellor
> On Wed, Jun 03, 2020 at 04:31:53PM -0700, Kees Cook wrote:
> > Using uninitialized_var() is dangerous as it papers over real bugs
> > (or can in the future), and suppresses unrelated compiler warnings
> > (e.g. "unused variable"). If the compiler thinks it is uninitialized,
> > either simply initialize the variable or make compiler changes.
> > As recommended by Linus, remove the macro.
> > Most of the 300 uses don't cause any warnings on gcc 9.3.0, so they're in
> > a single treewide commit in this series. A few others needed to actually
> > get cleaned up, and I broke those out into individual patches.
> > -Kees
> >  https://lore.kernel.org/lkml/20200603174714.192027-1-glider@xxxxxxxxxx/
> >  https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@xxxxxxxxxxxxxx/
> >  https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@xxxxxxxxxxxxxx/
> >  https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@xxxxxxxxxxxxxx/
> > Kees Cook (10):
> > x86/mm/numa: Remove uninitialized_var() usage
> > drbd: Remove uninitialized_var() usage
> > b43: Remove uninitialized_var() usage
> > rtlwifi: rtl8192cu: Remove uninitialized_var() usage
> > ide: Remove uninitialized_var() usage
> > clk: st: Remove uninitialized_var() usage
> > spi: davinci: Remove uninitialized_var() usage
> > checkpatch: Remove awareness of uninitialized_var() macro
> > treewide: Remove uninitialized_var() usage
> > compiler: Remove uninitialized_var() macro
> I applied all of these on top of cb8e59cc8720 and ran a variety of
> builds with clang for arm32, arm64, mips, powerpc, s390, and x86_64 
> and only saw one warning pop up (which was about a variable being
> unused, commented on patch 9 about it). No warnings about uninitialized
> variables came up; clang's -Wuninitialized was not impacted by
> 78a5255ffb6a ("Stop the ad-hoc games with -Wno-maybe-initialized") so it
> should have caught anything egregious.
> : https://github.com/nathanchance/llvm-kernel-testing
> For the series, consider it:
> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> [build]
I tried with updated version (checkpatch) of your tree and see no
(new) warnings in my build-log.
Feel free to add my...
Tested-by: Sedat Dilek <sedat.dilek@xxxxxxxxx>
- Sedat -