Re: [PATCH v6 1/3][Middle-end] Provide more contexts for -Warray-bounds, -Wstringop-*warning messages due to code movements from compiler transformation (Part 1) [PR109071,PR85788,PR88771,PR106762,PR108770,PR115274,PR117179]

[Qing Zhao]

> On Jun 27, 2025, at 15:24, Kees Cook <k...@kernel.org> wrote:
> 
> On Fri, Jun 27, 2025 at 01:38:51PM +0000, Qing Zhao wrote:
>> The good news is:  With the above simple heuristic and a simple back tracing 
>> of  the CFG, all the 
>> current testing cases for the following PRs passed without any issue:  
>> 
>> PR109071
>> PR88771
>> PR85788
>> PR108770
>> PR106762
>> PR115274
>> PR117179
>> 
>> I will continue working on this to add more testing cases and also more 
>> warnings per the following discussion:
>> https://gcc.gnu.org/pipermail/gcc-patches/2025-May/684126.html
>> https://gcc.gnu.org/pipermail/gcc-patches/2025-June/686323.html
>> https://gcc.gnu.org/pipermail/gcc-patches/2025-June/685852.html
>> https://gcc.gnu.org/pipermail/gcc-patches/2025-June/685854.html
>> 
>> Let me know if you have any comments or suggestions.
> 
> Thanks great!
> 
> Here are the patches I got landed in Linux that were uncovered using the
> earlier -fdiagnostics-details implementation:
> 
> https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?qt=grep&q=diagnostics-details
> 
> Reverting these patches show the warnings again for me. If you want to
> test them against the new implementation, this should work:
> 
> ### Set up build...
> 
> $ git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
> $ cd linux
> $ git revert --no-edit 8a39f1c870e9d6fbac5638f3a42a6a6363829c49
> $ git revert --no-edit 4a6f18f28627e121bd1f74b5fcc9f945d6dbeb1e
> $ git revert --no-edit 239d87327dcd361b0098038995f8908f3296864f
> $ git revert --no-edit ac6f0825e582f2216a582c9edf0cee7bfe347ba6
> $ CPUS=$(getconf _NPROCESSORS_ONLN)
> $ FLAGS="-Warray-bounds -fdiagnostic-show-context=1"
> $ make -j$CPUS KCFLAGS="$FLAGS" allmodconfig
> 
> # These three targets are stable, the 4th one is harder to hit, so
> # I've left it off (kernel/padata.o):
> 
> $ make -j$CPUS KCFLAGS="$FLAGS" fs/overlayfs/util.o
> $ make -j$CPUS KCFLAGS="$FLAGS" drivers/net/ethernet/mellanox/mlx4/alloc.o
> $ make -j$CPUS KCFLAGS="$FLAGS" drivers/pinctrl/mediatek/pinctrl-airoha.o

Thanks, I will try this with the new implementation on my side first.
> 
> 
> If you prefer, I can also do this once the new implementation is posted. :)

If there is any issue during my testing, I will let you know at that time.

Thanks a lot.

Qing
> 
> -Kees
> 
> -- 
> Kees Cook