Subject: bug#50355: [core-updates-frozen] Building mozjs with [email-masked] fails

From: Maxim Cournoyer <[email-masked]>
Date: Fri, 03 Sep 2021 07:17:20 -0400

Hello Guix!

I'm nearly done updating the Rust bootstrap for core-updates-frozen; one
of the changes is that only the current rust (1.54) gets exposed and
used everywhere.  This seems to be OK so far, except for mozjs, which
fails to build like so:

--8<---------------cut here---------------start------------->8---
error: aborting due to 8 previous errors

Some errors have detailed explanations: E0432, E0557.
For more information about an error, try `rustc --explain E0432`.
The following warnings were emitted during compilation:

warning: Cannot set `RUSTC_BOOTSTRAP=1` from build script of `packed_simd v0.3.3 (https://github.com/hsivonen/packed_simd?rev=3541e3818fdc7c2a24f87e3459151a4ce955a67a#3541e381)`.
note: Crates cannot set `RUSTC_BOOTSTRAP` themselves, as doing so would subvert the stability guarantees of Rust for your project.

error: could not compile `packed_simd`

Caused by:
--8<---------------cut here---------------end--------------->8---

If someone has an idea, please shout :-)

Thanks,

Maxim