Closed fmease closed 1 week ago
I think this was fixed at some point, presumably by #124566. However, it regressed again in #124418 (cc @compiler-errors) similar to #124702.
I presume #121848 will fail to build library/alloc
again after a rebase onto the latest master.
Context
This was minimized from
library/alloc
. Relevant to #121848 (the stabilization of-Znext-solver=coherence
).This is related to the open issue #124702 and the closed issue #124422. However, contrary to those, this issue represents a pass→ICE regression, not just an error→ICE one. Furthermore, it only uses the feature
min_specialization
(and not the more generalspecialization
) as it solely relies on assoc fn specialization (and not assoc type specialization).Reproducer
rustc allok.rs -Znext-solver=coherence
whereallok.rs
contains:Compiler Output
Full compiler output (incl. backtrace)
``` thread 'rustc' panicked at compiler/rustc_trait_selection/src/solve/eval_ctxt/canonical.rs:354:18: called `Result::unwrap()` on an `Err` value: Sorts(ExpectedFound { expected: (), found: str }) stack backtrace: 0: 0x7f3966b8cb55 - std::backtrace_rs::backtrace::libunwind::trace::h31c27f5cd8890956 at /rustc/e82c861d7e5ecd766cb0dab0bf622445dec999dc/library/std/src/../../backtrace/src/backtrace/libunwind.rs:105:5 1: 0x7f3966b8cb55 - std::backtrace_rs::backtrace::trace_unsynchronized::ha07b1f1ddca65445 at /rustc/e82c861d7e5ecd766cb0dab0bf622445dec999dc/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5 2: 0x7f3966b8cb55 - std::sys_common::backtrace::_print_fmt::h483b2f8f14ecd78e at /rustc/e82c861d7e5ecd766cb0dab0bf622445dec999dc/library/std/src/sys_common/backtrace.rs:68:5 3: 0x7f3966b8cb55 -Meta
HEAD~1
wrt. to an earlier iteration of PR #121848)