ICE: shouldn't have created a ValTree for *const ..

[matthiaskrgr]

auto-reduced (treereduce-rust):

struct NoDerive(i32);

#[derive(PartialEq)]
struct WrapEmbedded(*const NoDerive);

const WRAP_UNSAFE_EMBEDDED: &&WrapEmbedded = &&WrapEmbedded(std::ptr::null());

fn main() {
    match WRAP_UNSAFE_EMBEDDED {
        WRAP_UNSAFE_EMBEDDED => {}
        _ => {}
    }
}

original:

// Test explores how `#[structral_match]` behaves in tandem with
// `*const` and `*mut` pointers.

// run-pass

#![warn(pointer_structural_match)]

struct NoDerive(#[allow(unused_tuple_struct_fields)] i32);

// This impl makes NoDerive irreflexive
// (which doesn't matter here because `<*const T>::eq` won't recur on `T`).
impl PartialEq for NoDerive { fn eq(&self, _: &Self) -> bool { false } }

impl Eq for NoDerive { }

#[derive(PartialEq)]
struct WrapEmbedded(*const NoDerive);

const WRAP_UNSAFE_EMBEDDED: & &WrapEmbedded = & &WrapEmbedded(std::ptr::null());

fn main() {
    match WRAP_UNSAFE_EMBEDDED {
        WRAP_UNSAFE_EMBEDDED => { println!("WRAP_UNSAFE_EMBEDDED correctly matched itself"); }
        _ => { panic!("WRAP_UNSAFE_EMBEDDED did not match itself"); }
    }
}

Version information

rustc 1.77.0-nightly (2d7be7393 2023-12-23)
binary: rustc
commit-hash: 2d7be73931e0978c8758a672cc7258b417a7e999
commit-date: 2023-12-23
host: x86_64-unknown-linux-gnu
release: 1.77.0-nightly
LLVM version: 17.0.6

Command:
/home/matthias/.rustup/toolchains/master/bin/rustc

Program output

warning: to use a constant of type `WrapEmbedded` in a pattern, `WrapEmbedded` must be annotated with `#[derive(PartialEq, Eq)]`
  --> /tmp/icemaker_global_tempdir.9xUyew01Yauq/rustc_testrunner_tmpdir_reporting.KFwoDPkopCSi/mvce.rs:10:9
   |
10 |         WRAP_UNSAFE_EMBEDDED => {}
   |         ^^^^^^^^^^^^^^^^^^^^
   |
   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
   = note: for more information, see issue #62411 <https://github.com/rust-lang/rust/issues/62411>
   = note: the traits must be derived, manual `impl`s are not sufficient
   = note: see https://doc.rust-lang.org/stable/std/marker/trait.StructuralEq.html for details
   = note: `#[warn(indirect_structural_match)]` on by default

error: internal compiler error: compiler/rustc_const_eval/src/const_eval/valtrees.rs:404:14: shouldn't have created a ValTree for *const NoDerive

thread 'rustc' panicked at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/compiler/rustc_errors/src/lib.rs:1056:30:
Box<dyn Any>
stack backtrace:
   0:     0x7fbbfb78b6f6 - std::backtrace_rs::backtrace::libunwind::trace::h854d9901466ba2a6
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7fbbfb78b6f6 - std::backtrace_rs::backtrace::trace_unsynchronized::h2e5473e1358f3d7d
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fbbfb78b6f6 - std::sys_common::backtrace::_print_fmt::h17999543628ef5b9
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7fbbfb78b6f6 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::hd4a315f9d82cb167
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7fbbfb7ddf40 - core::fmt::rt::Argument::fmt::h61d1362a4781e5b2
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/core/src/fmt/rt.rs:142:9
   5:     0x7fbbfb7ddf40 - core::fmt::write::hdd3124965f70515e
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/core/src/fmt/mod.rs:1120:17
   6:     0x7fbbfb77f53f - std::io::Write::write_fmt::hf681a4235a84103e
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/io/mod.rs:1810:15
   7:     0x7fbbfb78b4d4 - std::sys_common::backtrace::_print::hf875b2182006ee31
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7fbbfb78b4d4 - std::sys_common::backtrace::print::h6091516d06acaa34
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7fbbfb78e267 - std::panicking::default_hook::{{closure}}::h7008dc256987fa65
  10:     0x7fbbfb78dfc9 - std::panicking::default_hook::he81ec00845e2991e
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/panicking.rs:292:9
  11:     0x7fbbfe55adec - std[76579cbcf5e75e71]::panicking::update_hook::<alloc[b53221f29dc7d1be]::boxed::Box<rustc_driver_impl[5725e9f2ae9a40a2]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7fbbfb78e9b6 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::hfccb34defa5e1891
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/alloc/src/boxed.rs:2029:9
  13:     0x7fbbfb78e9b6 - std::panicking::rust_panic_with_hook::ha947ff64165fedb2
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/panicking.rs:783:13
  14:     0x7fbbfe593a94 - std[76579cbcf5e75e71]::panicking::begin_panic::<rustc_errors[64d26b4b709225b4]::ExplicitBug>::{closure#0}
  15:     0x7fbbfe5901d6 - std[76579cbcf5e75e71]::sys_common::backtrace::__rust_end_short_backtrace::<std[76579cbcf5e75e71]::panicking::begin_panic<rustc_errors[64d26b4b709225b4]::ExplicitBug>::{closure#0}, !>
  16:     0x7fbbfe58fb86 - std[76579cbcf5e75e71]::panicking::begin_panic::<rustc_errors[64d26b4b709225b4]::ExplicitBug>
  17:     0x7fbbfe59e991 - <rustc_errors[64d26b4b709225b4]::diagnostic_builder::BugAbort as rustc_errors[64d26b4b709225b4]::diagnostic_builder::EmissionGuarantee>::emit_producing_guarantee
  18:     0x7fbbfe97152e - <rustc_errors[64d26b4b709225b4]::DiagCtxt>::bug::<alloc[b53221f29dc7d1be]::string::String>
  19:     0x7fbbfea0ca7b - rustc_middle[3892716d31dc4121]::util::bug::opt_span_bug_fmt::<rustc_span[d159d62802098cb3]::span_encoding::Span>::{closure#0}
  20:     0x7fbbfe9f5e1a - rustc_middle[3892716d31dc4121]::ty::context::tls::with_opt::<rustc_middle[3892716d31dc4121]::util::bug::opt_span_bug_fmt<rustc_span[d159d62802098cb3]::span_encoding::Span>::{closure#0}, !>::{closure#0}
  21:     0x7fbbfe9f5cb8 - rustc_middle[3892716d31dc4121]::ty::context::tls::with_context_opt::<rustc_middle[3892716d31dc4121]::ty::context::tls::with_opt<rustc_middle[3892716d31dc4121]::util::bug::opt_span_bug_fmt<rustc_span[d159d62802098cb3]::span_encoding::Span>::{closure#0}, !>::{closure#0}, !>
  22:     0x7fbbfc9a05a0 - rustc_middle[3892716d31dc4121]::util::bug::bug_fmt
  23:     0x7fbc001aa610 - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_into_mplace
  24:     0x7fbc001aa26c - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_into_mplace
  25:     0x7fbc001a9181 - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_to_ref
  26:     0x7fbc001aa4d0 - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_into_mplace
  27:     0x7fbc001a9181 - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_to_ref
  28:     0x7fbc000cd64e - rustc_const_eval[ea3edab3442d2e4]::const_eval::valtrees::valtree_to_const_value
  29:     0x7fbc000cd461 - <rustc_const_eval[ea3edab3442d2e4]::provide::{closure#1} as core[730ecc411c8eaf02]::ops::function::FnOnce<(rustc_middle[3892716d31dc4121]::ty::context::TyCtxt, (rustc_middle[3892716d31dc4121]::ty::Ty, rustc_middle[3892716d31dc4121]::ty::consts::valtree::ValTree))>>::call_once
  30:     0x7fbc000cd42e - rustc_query_impl[d4cc752ff0d73f28]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[d4cc752ff0d73f28]::query_impl::valtree_to_const_val::dynamic_query::{closure#2}::{closure#0}, rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 24usize]>>
  31:     0x7fbc000cd3f7 - <rustc_query_impl[d4cc752ff0d73f28]::query_impl::valtree_to_const_val::dynamic_query::{closure#2} as core[730ecc411c8eaf02]::ops::function::FnOnce<(rustc_middle[3892716d31dc4121]::ty::context::TyCtxt, (rustc_middle[3892716d31dc4121]::ty::Ty, rustc_middle[3892716d31dc4121]::ty::consts::valtree::ValTree))>>::call_once
  32:     0x7fbc000ccc92 - rustc_query_system[d117b86e449fcdf2]::query::plumbing::try_execute_query::<rustc_query_impl[d4cc752ff0d73f28]::DynamicConfig<rustc_query_system[d117b86e449fcdf2]::query::caches::DefaultCache<(rustc_middle[3892716d31dc4121]::ty::Ty, rustc_middle[3892716d31dc4121]::ty::consts::valtree::ValTree), rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[d4cc752ff0d73f28]::plumbing::QueryCtxt, false>
  33:     0x7fbc000cc9e4 - rustc_query_impl[d4cc752ff0d73f28]::query_impl::valtree_to_const_val::get_query_non_incr::__rust_end_short_backtrace
  34:     0x7fbbfd36ccc5 - <rustc_mir_transform[9620eec9afded333]::const_prop_lint::ConstPropagator as rustc_middle[3892716d31dc4121]::mir::visit::Visitor>::visit_operand
  35:     0x7fbbfd366c9e - <rustc_mir_transform[9620eec9afded333]::const_prop_lint::ConstPropagator as rustc_middle[3892716d31dc4121]::mir::visit::Visitor>::visit_basic_block_data
  36:     0x7fbbff9ffed2 - <rustc_mir_transform[9620eec9afded333]::const_prop_lint::ConstPropLint as rustc_mir_transform[9620eec9afded333]::pass_manager::MirLint>::run_lint
  37:     0x7fbbff862897 - rustc_mir_transform[9620eec9afded333]::run_analysis_to_runtime_passes
  38:     0x7fbbfd0469ff - rustc_mir_transform[9620eec9afded333]::mir_drops_elaborated_and_const_checked
  39:     0x7fbbff9ed635 - rustc_query_impl[d4cc752ff0d73f28]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[d4cc752ff0d73f28]::query_impl::mir_drops_elaborated_and_const_checked::dynamic_query::{closure#2}::{closure#0}, rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 8usize]>>
  40:     0x7fbbff9ed8c3 - rustc_query_system[d117b86e449fcdf2]::query::plumbing::try_execute_query::<rustc_query_impl[d4cc752ff0d73f28]::DynamicConfig<rustc_query_system[d117b86e449fcdf2]::query::caches::VecCache<rustc_span[d159d62802098cb3]::def_id::LocalDefId, rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[d4cc752ff0d73f28]::plumbing::QueryCtxt, false>
  41:     0x7fbbff9ed190 - rustc_query_impl[d4cc752ff0d73f28]::query_impl::mir_drops_elaborated_and_const_checked::get_query_non_incr::__rust_end_short_backtrace
  42:     0x7fbbfffed7aa - rustc_interface[1da9c7dc31a5385c]::passes::analysis
  43:     0x7fbbfffecf9d - rustc_query_impl[d4cc752ff0d73f28]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[d4cc752ff0d73f28]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 1usize]>>
  44:     0x7fbc0070f940 - rustc_query_system[d117b86e449fcdf2]::query::plumbing::try_execute_query::<rustc_query_impl[d4cc752ff0d73f28]::DynamicConfig<rustc_query_system[d117b86e449fcdf2]::query::caches::SingleCache<rustc_middle[3892716d31dc4121]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[d4cc752ff0d73f28]::plumbing::QueryCtxt, false>
  45:     0x7fbc0070f747 - rustc_query_impl[d4cc752ff0d73f28]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  46:     0x7fbc007a8b12 - rustc_interface[1da9c7dc31a5385c]::interface::run_compiler::<core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>, rustc_driver_impl[5725e9f2ae9a40a2]::run_compiler::{closure#0}>::{closure#0}
  47:     0x7fbc0072b486 - std[76579cbcf5e75e71]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[1da9c7dc31a5385c]::util::run_in_thread_with_globals<rustc_interface[1da9c7dc31a5385c]::util::run_in_thread_pool_with_globals<rustc_interface[1da9c7dc31a5385c]::interface::run_compiler<core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>, rustc_driver_impl[5725e9f2ae9a40a2]::run_compiler::{closure#0}>::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>
  48:     0x7fbc0072b2b3 - <<std[76579cbcf5e75e71]::thread::Builder>::spawn_unchecked_<rustc_interface[1da9c7dc31a5385c]::util::run_in_thread_with_globals<rustc_interface[1da9c7dc31a5385c]::util::run_in_thread_pool_with_globals<rustc_interface[1da9c7dc31a5385c]::interface::run_compiler<core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>, rustc_driver_impl[5725e9f2ae9a40a2]::run_compiler::{closure#0}>::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[730ecc411c8eaf02]::result::Result<(), rustc_span[d159d62802098cb3]::ErrorGuaranteed>>::{closure#1} as core[730ecc411c8eaf02]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  49:     0x7fbbfb7988e5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::hca712a7e6055e033
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/alloc/src/boxed.rs:2015:9
  50:     0x7fbbfb7988e5 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h0c4d9df2b2c66b37
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/alloc/src/boxed.rs:2015:9
  51:     0x7fbbfb7988e5 - std::sys::unix::thread::Thread::new::thread_start::h42e6b966712cbe95
                               at /rustc/2d7be73931e0978c8758a672cc7258b417a7e999/library/std/src/sys/unix/thread.rs:108:17
  52:     0x7fbbfb5849eb - <unknown>
  53:     0x7fbbfb6087cc - <unknown>
  54:                0x0 - <unknown>

note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md

note: rustc 1.77.0-nightly (2d7be7393 2023-12-23) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [valtree_to_const_val] converting type-level constant value to mir constant value
#1 [mir_drops_elaborated_and_const_checked] elaborating drops for `main`
#2 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 1 previous error; 1 warning emitted

[matthiaskrgr]

Regression in #116930 cc @RalfJung

[RalfJung]

Should be fixed by #119274.

[Noratrieb]

@rustbot label -needs-triage