Skip to content

building rustc with autodiff and debug enabled fails. #139704

Closed
@ZuseZ4

Description

@ZuseZ4

I tried this code:

./configure --enable-llvm-link-shared --enable-llvm-plugins --enable-llvm-enzyme --release-channel=nightly --enable-llvm-assertions --enable-clang --enable-lld --enable-option-checking --enable-ninja --disable-docs --enable-debug
./x.py build --stage 1 library

I expected to see this happen: builds rustc

Instead, this happened:

thread 'rustc' panicked at compiler/rustc_codegen_ssa/src/codegen_attrs.rs:57:9:
unexpected `def_kind` in `codegen_fn_attrs`: GlobalAsm

[...]

query stack during panic:
#0 [codegen_fn_attrs] computing codegen attributes of `probestack::{global_asm#0}`
#1 [collect_and_partition_mono_items] collect_and_partition_mono_items
... and 1 other queries... use `env RUST_BACKTRACE=1` to see the full query stack
error: could not compile `compiler_builtins` (lib)

Meta

rustc --version --verbose:

build from source

I know that debug builds used to work a few months ago.
So one could try to debug this by looking at the code. A much simpler solution probably is just
to do some binary search by building some older PR from the tracking issue with debug=true until finding one that builds. From there it should be easy to figure out which PR introduced the bug. Once that's clear it is hopefully easier to understand which change introduced the bug, and either directly fix it, or ask for help here or in the zulip channel. I'm marking it as easy, since it takes a bit of time to test multiple PRs but it isn't overly complex, and we had support for it and didn't introduce overly complex code changes in the last months. So the fix is likely also comparably simple.

This bug prevents us from enabling autodiff in CI and thus nightly, so any help would be appreciated!

Backtrace

<backtrace>

Metadata

Metadata

Assignees

Labels

C-bugCategory: This is a bug.E-easyCall for participation: Easy difficulty. Experience needed to fix: Not much. Good first issue.F-autodiff`#![feature(autodiff)]`

Type

No type

Projects

No projects

Milestone

No milestone

Relationships

None yet

Development

No branches or pull requests

Issue actions