Assertion fail in debug mode

[thomasyonug]

Code

// run-pass
#![allow(dead_code)]
#![allow(unused_variables)]
macro_rules! Tuple {
    { $A:ty,$B:ty } => { ($A, $B) }
}

fn main() {
    let x: Tuple!(i32, i32) = (1, 2);
}

fn issue_36540() {
    let _ = 0;
    macro_rules! m { () => { _ } }
    struct S<T = m!()>(m!(), T) where T: Trait<m!()>;

    let x: m!() = m!();
    std::cell::Cell::<m!()>::new(m!());
    impl<T> std::ops::Index<m!()> for dyn Trait<(m!(), T)>
        where T: Trait<m!()>
    {
        type Output = m!();
        fn index(&self, i: m!()) -> &m!() {
            unimplemented!()
        }
    }
}

trait Trait<T> {}
impl Trait<i32> for i32 {}

Meta

Error output

thread 'rustc' panicked at rust/compiler/rustc_errors/src/diagnostic.rs:642:9:
assertion `left == right` failed: suggestion must not have overlapping parts
  left: Some([SubstitutionPart { span: fuzz_input.rs:15:30: 15:31 (#5), snippet: "U" }, SubstitutionPart { span: fuzz_input.rs:15:30: 15:31 (#6), snippet: "U" }])
 right: None

Backtrace

stack backtrace:
   0: rust_begin_unwind
             at /rustc/0288f2e1955b154262e0669ec5f7bb9a4c6cf5aa/library/std/src/panicking.rs:597:5
   1: core::panicking::panic_fmt
             at /rustc/0288f2e1955b154262e0669ec5f7bb9a4c6cf5aa/library/core/src/panicking.rs:72:14
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed
             at /rustc/0288f2e1955b154262e0669ec5f7bb9a4c6cf5aa/library/core/src/panicking.rs:270:5
   4: rustc_errors::diagnostic::Diagnostic::multipart_suggestion_with_style
             at ./rust/compiler/rustc_errors/src/diagnostic.rs:642:9
   5: rustc_errors::diagnostic::Diagnostic::multipart_suggestion
             at ./rust/compiler/rustc_errors/src/diagnostic.rs:598:9
   6: rustc_errors::diagnostic_builder::DiagnosticBuilder<G>::multipart_suggestion
             at ./rust/compiler/rustc_errors/src/diagnostic_builder.rs:466:35
   7: rustc_hir_analysis::collect::placeholder_type_error_diag
             at ./rust/compiler/rustc_hir_analysis/src/collect.rs:236:13
   8: rustc_hir_analysis::collect::placeholder_type_error
             at ./rust/compiler/rustc_hir_analysis/src/collect.rs:169:5
   9: rustc_hir_analysis::collect::reject_placeholder_type_signatures_in_item
             at ./rust/compiler/rustc_hir_analysis/src/collect.rs:267:5
  10: <rustc_hir_analysis::collect::CollectItemTypesVisitor as rustc_hir::intravisit::Visitor>::visit_item
             at ./rust/compiler/rustc_hir_analysis/src/collect.rs:279:9
  11: rustc_middle::hir::map::Map::visit_item_likes_in_module
             at ./rust/compiler/rustc_middle/src/hir/map/mod.rs:606:13
  12: rustc_hir_analysis::collect::collect_mod_item_types
             at ./rust/compiler/rustc_hir_analysis/src/collect.rs:53:5
  13: rustc_query_impl::query_impl::collect_mod_item_types::dynamic_query::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_query_impl/src/plumbing.rs:585:47
      [... omitted 21 frames ...]
  14: rustc_middle::query::plumbing::query_ensure
             at ./rust/compiler/rustc_middle/src/query/plumbing.rs:172:9
  15: rustc_middle::query::<impl rustc_middle::query::plumbing::TyCtxtEnsure>::collect_mod_item_types
             at ./rust/compiler/rustc_middle/src/query/plumbing.rs:347:17
  16: rustc_hir_analysis::check_crate::{{closure}}::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_hir_analysis/src/lib.rs:171:48
  17: rustc_middle::hir::map::Map::for_each_module
             at ./rust/compiler/rustc_middle/src/hir/map/mod.rs:625:13
  18: rustc_hir_analysis::check_crate::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_hir_analysis/src/lib.rs:171:13
  19: rustc_data_structures::profiling::VerboseTimingGuard::run
             at ./rust/compiler/rustc_data_structures/src/profiling.rs:752:9
  20: rustc_session::utils::<impl rustc_session::session::Session>::time
             at ./rust/compiler/rustc_session/src/utils.rs:12:9
  21: rustc_hir_analysis::check_crate::{{closure}}
             at ./rust/compiler/rustc_hir_analysis/src/lib.rs:170:9
  22: rustc_session::session::Session::track_errors
             at ./rust/compiler/rustc_session/src/session.rs:578:22
  23: rustc_hir_analysis::check_crate
             at ./rust/compiler/rustc_hir_analysis/src/lib.rs:169:5
  24: rustc_interface::passes::analysis
             at ./rust/compiler/rustc_interface/src/passes.rs:775:5
  25: rustc_query_impl::query_impl::analysis::dynamic_query::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_query_impl/src/plumbing.rs:585:47
      [... omitted 21 frames ...]
  26: rustc_middle::query::plumbing::query_get_at
             at ./rust/compiler/rustc_middle/src/query/plumbing.rs:156:17
  27: rustc_middle::query::<impl rustc_middle::query::plumbing::TyCtxtAt>::analysis
             at ./rust/compiler/rustc_middle/src/query/mod.rs:2199:1
  28: rustc_middle::query::<impl rustc_middle::ty::context::TyCtxt>::analysis
             at ./rust/compiler/rustc_middle/src/query/plumbing.rs:377:35
  29: rustc_driver_impl::run_compiler::{{closure}}::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_driver_impl/src/lib.rs:446:52
  30: rustc_middle::ty::context::GlobalCtxt::enter::{{closure}}
             at ./rust/compiler/rustc_middle/src/ty/context.rs:598:37
  31: rustc_middle::ty::context::tls::enter_context::{{closure}}
             at ./rust/compiler/rustc_middle/src/ty/context/tls.rs:82:9
  32: std::thread::local::LocalKey<T>::try_with
             at /rustc/0288f2e1955b154262e0669ec5f7bb9a4c6cf5aa/library/std/src/thread/local.rs:270:16
  33: std::thread::local::LocalKey<T>::with
             at /rustc/0288f2e1955b154262e0669ec5f7bb9a4c6cf5aa/library/std/src/thread/local.rs:246:9
  34: rustc_middle::ty::context::tls::enter_context
             at ./rust/compiler/rustc_middle/src/ty/context/tls.rs:79:9
  35: rustc_middle::ty::context::GlobalCtxt::enter
             at ./rust/compiler/rustc_middle/src/ty/context.rs:598:9
  36: rustc_driver_impl::run_compiler::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_driver_impl/src/lib.rs:446:13
  37: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter
             at ./rust/compiler/rustc_interface/src/queries.rs:373:19
  38: rustc_driver_impl::run_compiler::{{closure}}
             at ./rust/compiler/rustc_driver_impl/src/lib.rs:387:22
  39: rustc_interface::interface::run_compiler::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_interface/src/interface.rs:346:21
  40: rustc_span::set_source_map
             at ./rust/compiler/rustc_span/src/lib.rs:1063:5
  41: rustc_interface::interface::run_compiler::{{closure}}
             at ./rust/compiler/rustc_interface/src/interface.rs:340:13
  42: scoped_tls::ScopedKey<T>::set
             at /home/ywz/.cargo/registry/src/index.crates.io-6f17d22bba15001f/scoped-tls-1.0.1/src/lib.rs:137:9
  43: rustc_span::create_session_globals_then
             at ./rust/compiler/rustc_span/src/lib.rs:123:5
  44: rustc_interface::util::run_in_thread_with_globals::{{closure}}::{{closure}}
             at ./rust/compiler/rustc_interface/src/util.rs:163:38