Hi, Kees, I will study this testing case to see what is missing there. And update if I found anything.
thanks. Qing > On Jun 5, 2025, at 19:49, Kees Cook <k...@kernel.org> wrote: > > On Thu, Jun 05, 2025 at 03:52:21PM -0700, Kees Cook wrote: >> On Mon, May 19, 2025 at 11:23:34AM -0700, Kees Cook wrote: >>> On Fri, May 16, 2025 at 01:34:14PM +0000, Qing Zhao wrote: >>>> Adding -fdiagnotics-details into GCC to provide more hints to the >>>> end users on how the warnings come from, in order to help the user >>>> to locate the exact location in source code on the specific warnings >>>> due to compiler optimizations. >>> >>> I just needed to examine an unexpected -Wrestrict warning, and >>> discovered that this patch didn't help with it, but in looking at the >>> implementation details, it turned out to be trivial to expand coverage >>> to include -Wrestrict, which worked for me, and got me the >>> diagnostics I needed[1]. >> >> I found another case[1] where I didn't get detailed diagnostics, so I >> tried to instrument that too, but it didn't do anything. Here's the patch >> (trying to get more coverage for stringop-overflow), but I don't know >> what I did wrong: > > I think this may be a known bug. It looks very similar to this: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97490 > and is somehow related to -fsanitize=kernel-address > > -- > Kees Cook