Re: snek testsuite breaks in 10.1 for qemu-system-arm on armhf

["Alex Bennée" <alex.bennee@linaro.org>]

Christian Ehrhardt <christian.ehrhardt@canonical.com> writes:

(adding qemu-arm and Richard to the CC)

> Hi,
> Debian and Ubuntu run the self tests of snek as integration tests like:
>
> `make SNEK_NATIVE=/usr/bin/snek SNEK_ARM=/usr/share/snek/snek-arm
> SNEK_RISCV=/usr/share/snek/snek-riscv -C test check`
>
> Those tests recently generated signal by failing in the arm emulation
> tests with `qemu-system-arm` - full log [1].
>
> ```
> 224s Running test pass-precedence.py.
> 224s     pass python3
> 224s     pass snek
> 224s pass-precedence.py:72 Syntax error at "".
> 224s     ***************** snek-arm fail *********************
> 224s     pass snek-riscv
> ```
>
> 14 tests failed, but all with quite similar signatures.
>
> But that only happens when executed on armhf, the other host
> architectures are all happy [2].
>
> I've separated the test and ran a git bisect on qemu 10.0 -> 10.1 as
> somewhere here is the trigger.
> That worked fine and identified this change [3].

This is:

  tcg: Convert deposit to TCGOutOpDeposit

  Reviewed-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
  Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

> I must admit, I was able to debug it until here, but I can't see how
> these snek test failures could be caused by that change.
> And yes - arm emulation on an armhf platform isn't the most common
> scenario.

Are any of your other hosts 32 bit?

>
> I can't predict if there is anything wrong in snek which now is
> treated differently by qemu to trigger this or if snek is all fine and
> qemu broken something - Therefore I've also reported it to snek [4].
>
> The tracking of the initial finding in Ubuntu is here if you want to
> see more about how this commit was identified [5].
>
> [1]: https://autopkgtest.ubuntu.com/results/autopkgtest-questing/questing/armhf/s/snek/20250818_045020_246a4@/log.gz
> [2]: https://autopkgtest.ubuntu.com/packages/s/snek
> [3]: https://salsa.debian.org/qemu-team/qemu/-/commit/cf4905c03135f1181e86c618426f8d6c703b38c0
> [4]: https://github.com/keith-packard/snek/issues/103
> [5]: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/2121124

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro