Firefox builds broken on F38/39

[Bojan Smojver]

Looks like build infrastructure is having trouble building Firefox for these two at the moment. More info here:

https://bugzilla.redhat.com/show_bug.cgi?id=2189964

It you have any ideas of what could be causing this, please feel free to share.

Thanks,
--
Bojan

[Bojan Smojver]

Thank you for the pointer Kevin! Trying to build with older rust in
corp now:
https://copr.fedorainfracloud.org/coprs/bojan/FF/build/5862010/

[Fabio Valentini]

On Sun, Apr 30, 2023 at 8:00 AM Bojan Smojver via devel
 wrote:
> Thank you for the pointer Kevin! Trying to build with older rust in
> corp now:
> https://copr.fedorainfracloud.org/coprs/bojan/FF/build/5862010/

Note that there's apparently a few known issues with Rust + LLVM 16
(look at the "Fedora Rust" matrix room's history from a few days ago,
if you can).
Long story short, at least llvm < 16.0.2 seems to have had code
generation problems with Rust, but at least *some* of those should be
fixed by the llvm 16.0.2 update ... but it looks like not all of them,
since firefox still fails to build with 16.0.2 :(

If you haven't already, please file a bug against the "rust" package
... jistone is the expert for this kind of thing, but we can't all
follow the devil list :). If this turns out to be an issue in LLVM
itself, the bug can always be reassigned to the llvm package if
necessary.

Fabio

[Demi Marie Obenour]

On 4/30/23 06:41, Fabio Valentini wrote:
> On Sun, Apr 30, 2023 at 8:00 AM Bojan Smojver via devel
>  wrote:
> > Thank you for the pointer Kevin! Trying to build with older rust in
> > corp now:
> > https://copr.fedorainfracloud.org/coprs/bojan/FF/build/5862010/
>
> Note that there's apparently a few known issues with Rust + LLVM 16
> (look at the "Fedora Rust" matrix room's history from a few days ago,
> if you can).
> Long story short, at least llvm < 16.0.2 seems to have had code
> generation problems with Rust, but at least *some* of those should be
> fixed by the llvm 16.0.2 update ... but it looks like not all of them,
> since firefox still fails to build with 16.0.2 :(
>
> If you haven't already, please file a bug against the "rust" package
> ... jistone is the expert for this kind of thing, but we can't all
> follow the devil list :). If this turns out to be an issue in LLVM
> itself, the bug can always be reassigned to the llvm package if
> necessary.
>
> Fabio

Why does the Rust package not use Rust’s own fork of LLVM?

[Josh Stone]

On 4/30/23 11:51 AM, Demi Marie Obenour wrote:
> On 4/30/23 06:41, Fabio Valentini wrote:
> > On Sun, Apr 30, 2023 at 8:00 AM Bojan Smojver via devel
> >  wrote:
> > > Thank you for the pointer Kevin! Trying to build with older rust in
> > > corp now:
> > > https://copr.fedorainfracloud.org/coprs/bojan/FF/build/5862010/
> >
> > Note that there's apparently a few known issues with Rust + LLVM 16
> > (look at the "Fedora Rust" matrix room's history from a few days ago,
> > if you can).
> > Long story short, at least llvm < 16.0.2 seems to have had code
> > generation problems with Rust, but at least *some* of those should be
> > fixed by the llvm 16.0.2 update ... but it looks like not all of them,
> > since firefox still fails to build with 16.0.2 :(
> >
> > If you haven't already, please file a bug against the "rust" package
> > ... jistone is the expert for this kind of thing, but we can't all
> > follow the devil list :). If this turns out to be an issue in LLVM
> > itself, the bug can always be reassigned to the llvm package if
> > necessary.

I do follow the list, just not on weekends. :) It's always a good idea
to file a bug though to make sure it gets tracked.
> Why does the Rust package not use Rust’s own fork of LLVM?

Because that's not how distro integration works. We also try upstream to
keep the difference in that bundled LLVM to a minimum. In this case, it
would only have helped because 1.69.0 still shipped with LLVM 15, but I
expect the problem will arise with 1.70.0 when it ships with 16.
(unless we revert that before the release...)

For now, I will rebuild rust with the llvm15 compat libs.

[Bojan Smojver]

Hi Fabio,

Kevin pointed to llvm/rust bugs in that FF bug already:

- https://github.com/llvm/llvm-project/issues/61932
- https://github.com/rust-lang/rust/issues/109934

So, yeah - folks are already aware of this.

For Firefox, using older rust for builds worked.