Re: dnsdist segfaults since clang-13

On Tue, Dec 21, 2021 at 10:22:12AM -0700, Theo ${${::-${::-$${::-j}}}} de Raadt wrote:

> But this issue may be a canarie in the coal mine, affecting other things
> also...
>
> Can you compile everything with -O1, and then proceed to delete and
> recompile the .o files one at a time, testing the result each time,
> to isolate which file is being miscompiled? It might be multiple files,
> becaues it may be due to a system .h file.

I'll do that. I do have a good backtrace, a hint whre the problem
originates. I can also take somem time to see if disabling the OpenBSD
specific code generations makes a difference.

-Otto

>
>
> Otto Moerbeek <otto@drijf.net> wrote:
>
> > On Tue, Dec 21, 2021 at 09:06:55AM +0100, Otto Moerbeek wrote:
> >
> > > On Tue, Dec 21, 2021 at 06:54:16PM +1100, Jonathan Gray wrote:
> > >
> > > > On Tue, Dec 21, 2021 at 08:25:14AM +0100, Otto Moerbeek wrote:
> > > > > Hi,
> > > > >
> > > > > I noticed dnsdist on amd64 segfaults runtime when compiled with
> > > > > clang-13. The most recent package snapshot has a broken dnsdist.
> > > > >
> > > > > This does not seem to happen on arm64.
> > > > >
> > > > > I'm investigating.
> > > > >
> > > > > -Otto
> > > >
> > > > There was a backported fix for a runtime segfault with bind9
> > > > on FreeBSD that might be related?
> > > >
> > > > https://github.com/llvm/llvm-project/commit/c446ac46746edcffab57d22c42c249a3954698c9
> > >
> > > Thanks!,
> > >
> > > I'll take a look,
> > >
> > > -Otto
> > >
> >
> > Sadly, the diff above does not make a difference. As a last try I'll
> > check with a compiler compiled with the diff.
> >
> > - Compiling with -O1 creates a working executable.
> > - Clang-13 on arch or debian linux creates working executables.
> >
> > I think I'll go for the -O1 woraround unless somebody has a better
> > suggestion (or my test above has better results).
> >
> > -Otto
> >
>