search

rust-lang / backtrace-rs

Backtraces in Rust
https://docs.rs/backtrace
Other
516 stars 237 forks source link

Whitespace trigger CI #594

Closed workingjubilee closed 3 months ago

workingjubilee commented 3 months ago

@ChrisDenton hypothesized in https://github.com/rust-lang/rust/issues/122857 that our CI should catch brokenness. But we haven't run our CI in a couple nights. Let's see what happens!

ChrisDenton commented 3 months ago

Oh, ha it does show up in our CI.

workingjubilee commented 3 months ago

build/host/stage0-sysroot/bin/rustc: error while loading shared libraries: libLLVM.so.18.1-rust-1.78.0-beta: cannot open shared object file: No such file or directory

that's odd...

but yeah!

On the other hand, this is also pretty conclusive proof that it's sometime in the past few nightlies.

ChrisDenton commented 3 months ago

Oh hm, it's a "without_debuginfo" test that's failing? Maybe I'm missing something but I would expect having no debuginfo to not have symbols otherwise where are the symbols coming from? Am confused.

workingjubilee commented 3 months ago

@ChrisDenton shouldn't a backtrace on Windows succeed in symbolication for the system libraries?

ChrisDenton commented 3 months ago

It does have BaseThreadInitThunk and RtlUserThreadStart. Which is what I'd expect.

workingjubilee commented 3 months ago

@ChrisDenton then how did the test ever pass before?

ChrisDenton commented 3 months ago

Maybe rustc was lying and actually did produce some minimal debug info? As I say, I'm confused.

workingjubilee commented 3 months ago

Probably something like that. Probably the test is poorly named. What we do know is that these tests also failed: https://github.com/lightningdevkit/rust-lightning/actions/runs/8379442307/job/22946366702?pr=2954

ChrisDenton commented 3 months ago

Hm, the backtrace test fails on stable for me, not just beta as reported. Might be a different issue? Running cargo-bisect failed not sure why. In any case a manual bisect shows it succeeding in nightly-2024-01-17 but failing in nightly-2024-01-18.

> git log --oneline --ancestry-path 098d4fd74..6ae4cfbbb 
6ae4cfbbb08 Auto merge of #118708 - davidtwco:target-tier-assembly-test, r=Mark-Simulacrum
c58a5da7d48 Auto merge of #119930 - Urgau:check-cfg-empty-values-means-empty, r=petrochenkov
52790a98e56 Auto merge of #119670 - cjgillot:gvn-arithmetic, r=oli-obk
12c19a2bb77 target: fix powerpc64-unknown-linux-musl datalayout
a87034c2977 tests: add sanity-check assembly test for every target
25b706cde3e Auto merge of #119111 - michaelwoerister:measureme-11, r=Mark-Simulacrum
16f4b02dd8a Auto merge of #119922 - nnethercote:fix-Diag-code-is_lint, r=oli-obk
f45fe573a58 Auto merge of #119651 - novafacing:proc_macro_c_str_literals, r=Amanieu
6bf600bc988 Auto merge of #120019 - lcnr:fn-wf, r=BoxyUwU
6ed31aba1a8 Auto merge of #120036 - weihanglo:update-cargo, r=weihanglo

Only thing that sticks out is the cargo update, which contains this PR: https://github.com/rust-lang/cargo/pull/13257. It strips debug info from std if debug information is not otherwise needed.

And indeed if I set strip = false in the test's Cargo.toml then it succeeds. We could do that so the test goes back to testing what it used. I'm still not sure what the intent of this test is though.

workingjubilee commented 3 months ago

honestly I'm not entirely sure either!!

workingjubilee commented 3 months ago

but people were relying on these backtraces working... hm.

workingjubilee commented 3 months ago

...also why does that test now ONLY break on Windows?

ChrisDenton commented 3 months ago

Hmm....

workingjubilee commented 3 months ago

and why doesn't rustc run similar tests???

ChrisDenton commented 3 months ago

It seems that for msvc we pass /DEBUG:none (i.e. don't make a pdb file) if any strip option is chosen. https://github.com/rust-lang/rust/blob/cdb683f6e4b0774b85c60eebe12af87f29d8ee4d/compiler/rustc_codegen_ssa/src/back/linker.rs#L968

Whereas on gnu targets we can choose to include symbols only https://github.com/rust-lang/rust/blob/cdb683f6e4b0774b85c60eebe12af87f29d8ee4d/compiler/rustc_codegen_ssa/src/back/linker.rs#L625.

workingjubilee commented 3 months ago

urgh, but that's not really the desired semantics for a natively split-debuginfo platform, is it?

ChrisDenton commented 3 months ago

I left a comment on the rustc issue. This feels very much like a rustc or cargo thing to sort out between them. 🙂

ChrisDenton commented 3 months ago

Also, are we not testing beta and nightly on Windows? That should surely have caught this earlier.

workingjubilee commented 3 months ago

We apparently are not. Yes, it would have.

workingjubilee commented 3 months ago

anyways thanks for coming folks!