Collect panic/panic_bounds_check during monomorphization

[nbdd0121]

This would prevent link time errors if these functions are #[inline] (e.g. when panic_immediate_abort is used).

Fix #90405
Fix rust-lang/cargo#10019

@rustbot label: T-compiler A-codegen

[rust-highfive]

r? @cjgillot

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[tmiasko]

Wouldn't the eager mode consider panic function to be one of roots and hide the bug?

[nbdd0121]

Fixed. Good catch!

[cjgillot]

Thanks @nbdd0121! LGTM.

Instance::mono will panic if the function has generics.
What happens if the input program (erroneously) declares the panic lang item function to have generic parameters?

#[lang = "panic"]
fn panic<T>(_: T) -> ! { loop {} }

Is this error correctly caught by lang item check or does Instance::mono ICE.

[nbdd0121]

Is this error correctly caught by lang item check or does Instance::mono ICE.

It'll ICE. But it will ICE regardless this change since rustc_codegen_ssa uses Instance::mono to create an instance of panic as well.

[nbdd0121]

(with that said this is a very simple check so added it anyway)

[cjgillot]

@bors r+

[bors]

📌 Commit 4d619d9 has been approved by cjgillot

[bors]

⌛ Testing commit 4d619d9 with merge db062de...

[bors]

☀️ Test successful - checks-actions
Approved by: cjgillot
Pushing db062de to master...

[rust-timer]

Finished benchmarking commit (db062de): comparison url.

Summary: This benchmark run did not return any relevant changes.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

@rustbot label: -perf-regression