Re: [musl] waitpid (wait4) on Linux 5 returns invalid values

[Rasmus Andersson <rasmus@notion.se>]

Zach I'm glad I was able to help! No trouble at all.
Thank you all for your work on musl & accompanying tools :-)

On Tue, Jan 19, 2021 at 3:01 PM Zach van Rijn <me@zv.io> wrote:
>
> On Tue, 2021-01-19 at 14:02 -0800, Rasmus Andersson wrote:
> > The program compiles correctly with
> > https://more.musl.cc/9/x86_64-linux-musl/x86_64-linux-musl-native.tgz
> > (The GCC 9 version) Perhaps an issue with GCC 10?
>
> Rasmus, thank you for reporting this issue.
>
>
> Using your reproducer I'm able to observe the following:
>
> (1) GCC 10 as-published on musl.cc : BUG
> waitpid returned -10, wstat=0, errno=0 (No error information)
>
> (2) GCC 10 without this patch [1]  : OK
> waitpid returned -1, wstat=0, errno=10 (No child process)
>
> which matches your GCC 9 (20200828) observation.
>
>
> This patch was applied to musl.cc as part of a series to add
> experimental riscv32 support in September 2020, but was applied
> universally and not strictly riscv32 targets.
>
> The patch in question was /not/ applied to the GCC 9 binaries as
> they were last updated in August of 2020, nor to earlier 10 ones.
>
> I am updating the build infrastructure to avoid contamination of
> "supported" targets by experimental patches such as this one.
>
> New (fixed and newer GCC) toolchains will be published as soon as
> they finish building (~24 hours). I will ping you off-list.
>
> Additional tests (not simply spot-checks) will be implemented for
> future releases.
>
>
> Sorry for the inconvenience.
>
>
> [1]: https://www.openwall.com/lists/musl/2020/09/03/14
>