Re: [XEN PATCH] automation: Avoid changing source files for randconfig tests

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 27 Mar 2025, Anthony PERARD wrote:
> On Wed, Mar 26, 2025 at 07:10:52PM -0700, Stefano Stabellini wrote:
> > On Wed, 26 Mar 2025, Anthony PERARD wrote:
> > > diff --git a/automation/scripts/build b/automation/scripts/build
> > > index 522efe774e..8a3b8fb6b2 100755
> > > --- a/automation/scripts/build
> > > +++ b/automation/scripts/build
> > > @@ -12,12 +12,12 @@ $cc --version
> > >  # random config or default config
> > >  if [[ "${RANDCONFIG}" == "y" ]]; then
> > >  
> > > -    # Append job-specific fixed configuration
> > > -    if [[ -n "${EXTRA_FIXED_RANDCONFIG}" ]]; then
> > > -        echo "${EXTRA_FIXED_RANDCONFIG}" >> 
> > > xen/tools/kconfig/allrandom.config
> > > -    fi
> > > +    cp -f xen/tools/kconfig/allrandom.config xen/allrandom.config.tmp
> > 
> > Wouldn't it be better to use mktemp?
> > 
> > local tmpconfig=$(mktemp)
> 
> I though of it and I wasn't sure if we could use it in the CI, but it's
> already been used so that's an option. (Actually, there's only a single
> use by ./check-endbr.sh, ./configure does use it as well but to create
> temporary directory within the build tree.)
> 
> But, to avoid overflowing /tmp with loads of leftover temporary files,
> we need to clean it, with:
> 
>     trap "rm $tmpconfig" EXIT
> 
> The advantage of using an in-tree files with a predefined name is that
> it isn't going to create more than one file, no matter how many time you
> run ./build. The '*.tmp' files are already ignored by our .gitignore. I
> could rename it to with a "." to hide it a bit more.

I think it is fine, there is no need to hide them more.

I was suggesting to create a file under /tmp instead to keep the source
directory cleaner, and also because I don't think it is an issue to add
files to /tmp and not clean them because they get removed when the
container exits. Isn't it the case? Locally it looks like each
containers gets its own /tmp that is cleaned after exit.

So my preference is to use mktemp and *not* clean the tmp file on exit.

If you think we have to clean the tmp file on exit, then let's go with
your xen/allrandom.config.tmp approach as I would prefer to avoid the
"trap" command to keep the sources simpler.