panic in constant evaluation while documenting default associated constant #149635
Description
Code
This is similar to #131625, but it used to work until recently:
#[repr(C)] #[derive(Debug, Default, Copy, Clone)] pub struct VMStateFlags(pub u32); impl VMStateFlags { pub const VMS_POINTER: VMStateFlags = VMStateFlags(2); } #[repr(C)] #[derive(Debug, Default, Copy, Clone)] pub struct VMStateField { pub flags: VMStateFlags, } pub unsafe trait VMState { const BASE: VMStateField; const VARRAY_FLAG: VMStateFlags = { panic!("invalid type for variable-sized array"); }; }With rustdoc 1.91.1 and 1.92.0-beta.3 (f3f1244 2025-11-09), this works:
$ /usr/bin/rustdoc --edition=2021 --crate-name vmstate vmstate.rs -o doc With rustdoc 1.93.0-nightly (83e49b7 2025-12-03), I get evaluation panicked.
Version it worked on
1.91.1
1.92.0-beta.3 (f3f1244 2025-11-09)
Version with regression
1.93.0-nightly (83e49b7 2025-12-03)
rustc --version --verbose:
rustc 1.93.0-nightly (83e49b75e 2025-12-03) binary: rustc commit-hash: 83e49b75e7daf827e4390ae0ccbcb0d0e2c96493 commit-date: 2025-12-03 host: x86_64-unknown-linux-gnu release: 1.93.0-nightly LLVM version: 21.1.5 @rustbot modify labels: +regression-from-stable-to-nightly -regression-untriaged