Stabilizing panic_immediate_abort

[mwcampbell]

Forgive me if there's already a tracking issue for this, but I haven't been able to find one. I see that the build script for the precompiled serde_derive binary uses this feature (and thus a nightly toolchain), so there's clearly demand for it. How can we users help get it stabilized?

[ChrisDenton]

serde_derive is using the build-std feature. See: https://github.com/serde-rs/serde/blob/bfcd44704f847ac5a9f3072e102e803b5ebbef31/precompiled/build.sh#L12-L14

This is where the standard library is rebuilt instead of using the pre-built rlibs. It is unlikely that build-std is going to be stabilized any time soon but if you'd like to help out or track its progress then see https://github.com/rust-lang/wg-cargo-std-aware/issues

[ChrisDenton]

That said, I would ask why you want it stabilized? There may be other designs that may achieve your goals.

For example, I have previously discussed with some devs that I'd love a way to turn off std backtraces and that whole machinery. Perhaps a rustc flag like -C backtrace=off, or maybe an attribute similar to global_alloc that allows plugging in your own backtrace stuff (which could just be a empty function). But I need to get round to writing up a proposal and figuring out the details.

[mwcampbell]

A way to override the panic handler while still using std, as one can override the global allocator, would be good enough for me.

[bjorn3]

This can't be stabilized without also stabilizing rebuilding the standard library in the first place, which still has basic issues like trying to compile with panic = "abort" on a panic=unwind target being broken.

[ChrisDenton]

Closing this as I think stabilizing build-std features are better tracked as part of that effort. Happy to reopen if people disagree.

[ruuda]

Is there an issue I can subscribe to for staying up to date with the stabilization effort? I was able to find that build-std is part of https://github.com/rust-lang/wg-cargo-std-aware, but I don’t see an issue about panic_immediate_abort there.