Re: [Bug 1883560] [NEW] mips linux-user builds occasionly crash randomly only to be fixed by a full clean re-build

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

Cornelia Huck <cohuck@redhat.com> writes:

> On Thu, 18 Jun 2020 19:00:34 +0200
> Aleksandar Markovic <aleksandar.qemu.devel@gmail.com> wrote:
>
>> четвртак, 18. јун 2020., Cornelia Huck <cohuck@redhat.com> је написао/ла:
>> 
>> > On Mon, 15 Jun 2020 15:18:48 -0000
>> > Alex Bennée <1883560@bugs.launchpad.net> wrote:
>> >  
>> > > Public bug reported:
>> > >  
>> > > >From time to time I find check-tcg crashes with a one of the MIPS  
>> > > binaries. The last time it crashed was running the test:
>> > >
>> > >   ./mips64el-linux-user/qemu-mips64el ./tests/tcg/mips64el-linux-
>> > > user/threadcount
>> > >
>> > > Inevitably after some time noodling around wondering what could be
>> > > causing this weird behaviour I wonder if it is a build issue. I wipe all
>> > > the mips* build directories, re-run configure and re-build and voila
>> > > problem goes away.
>> > >
>> > > It seems there must be some sort of build artefact which isn't being
>> > > properly re-generated on a build update which causes weird problems.
>> > > Additional data point if I:
>> > >
>> > >   rm -rf mips64el-linux-user
>> > >   ../../configure
>> > >   make
>> > >
>> > > then I see failures in mip32 builds - eg:
>> > >
>> > >     GEN     mipsn32el-linux-user/config-target.h
>> > >   In file included from /home/alex/lsrc/qemu.git/  
>> > linux-user/syscall_defs.h:10,  
>> > >                    from /home/alex/lsrc/qemu.git/linux-user/qemu.h:16,
>> > >                    from /home/alex/lsrc/qemu.git/  
>> > linux-user/linuxload.c:5:  
>> > >   /home/alex/lsrc/qemu.git/linux-user/mips64/syscall_nr.h:1: error:  
>> > unterminated #ifndef  
>> > >    #ifndef LINUX_USER_MIPS64_SYSCALL_NR_H
>> > >
>> > >   make[1]: *** [/home/alex/lsrc/qemu.git/rules.mak:69:  
>> > linux-user/linuxload.o] Error 1  
>> > >   make[1]: *** Waiting for unfinished jobs....
>> > >
>> > > which implies there is a cross dependency between different targets
>> > > somewhere. If I executed:
>> > >
>> > >   rm -rf mips*
>> > >
>> > > before re-configuring and re-building then everything works again.
>> > >
>> > > ** Affects: qemu
>> > >      Importance: Undecided
>> > >          Status: New
>> > >
>> > >
>> > > ** Tags: build linux-user mips
>> > >  
>> >
>> > FWIW, this does not seem to be a mips-only issue: I'm seeing the
>> > threadcount test fail with s390x-linux-user as well, and it also goes
>> > away (only) if I purge the build directory, re-configure, and re-build.
>> >
>> >
>> >  
>> Alex, Cornelia,
>> 
>> Do you perhaps recall how did you obtain the original binaries (those with
>> the problem)? What would be your typical workflow? Perhaps "git-pull +
>> make" on existing, but not latest source tree?
>
> Just a bog-standard "pull some stuff, do make, create a branch and put
> some patches on it, do make, switch to another branch, do make, etc". No
> advanced fiddling with git history, doing make on a subtree, etc.

Same here. As I say the syscall_nr breakage was a different one. I'll
regularly just advance my tree and find this sort of breakage.

-- 
Alex Bennée