ice: `attempted .def_id() on invalid res: Err`

[matthiaskrgr]

auto-reduced (treereduce-rust):

#[repr(C)]



#[repr(C)]
struct Bar {
    _: union {
        a: u8,
    },
}




#[repr(C)]




#[repr(C)]




#[repr(C)]
union C {
    _: struct {
        _: union {
            
              ,
        },

        
          union  ,
    },
    
      union ,
}



#[repr(C)]
struct D {
    
    _: Foo,

    
    a: u8, 
    
    _: union {
        a: u8, 
    }  union ,
}



#[repr(C)]
union D2 {
    
    _: Bar,

    
    a: u8, 
    
    _: union {
        a: u8, 
    }  union ,
}



#[repr(C)]
struct E {
    _: struct {
        
        ,

        
        , 
        
          union  ,
    },

    
      union ,
}


#[repr(C)]

union E2 {
    _: struct {
        
        ,

        
        , 
        
          union  ,
    },

    
      union ,
}

original code

original:

#![allow(incomplete_features)]
#![feature(unnamed_fields)]

#[derive{
        pub a: u8
    }]
#[repr(C)]
struct Foo {
    a: u8,
}

#[derive(Clone, Copy)]
#[repr(C)]
struct Bar {
    _: union {
        a: u8,
    },
}


// duplicated with a normal field
#[derive(Clone, Copy)]
#[repr(C)]
union A {
    // referent field
    a: u8,

    // normal field
    a: u8, //~ ERROR field `a` is already declared [E0124]
    // nested field
    _: struct {
        a: u8, //~ ERROR field `a` is already declared [E0124]
        a: u8, //~ ERROR field `a` is already declared [E0124]
    },
    // more nested field
    _: union {
        _: struct {
            a: u8, //~ ERROR field `a` is already declared [E0124]
        },
    },
    // nested field in a named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: struct {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a nested field
#[derive(Clone, Copy)]
#[repr(C)]
struct B {
    _: union {
        // referent field
        a: u8,

        // normal field (within the same anonymous adt)
        a: u8, //~ ERROR field `a` is already declared [E0124]
        // nested field (within the same anonymous adt)
        _: struct {
            a: u8, //~ ERROR field `a` is already declared [E0124]
        },
        // more nested field (within the same anonymous adt)
        _: union {
            _: struct {
                a: u8, //~ ERROR field `a` is already declared [E0124]
            },
        },
        // nested field in a named adt (within the same anonymous adt)
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
        // nested field in a named adt in an anoymous adt (within the same anonymous adt)
        _: struct {
            _: Foo, //~ ERROR field `a` is already declared
            _: Bar, //~ ERROR field `a` is already declared
        },
    },

    // normal field
    a: u8, //~ ERROR field `a` is already declared [E0124]
    // nested field
    _: struct {
        a: u8, //~ ERROR field `a` is already declared [E0124]
    },
    // more nested field
    _: union {
        _: struct {
            a: u8, //~ ERROR field `a` is already declared [E0124]
        },
    },
    // nested field in a named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: struct {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a more nested field
#[derive(Clone, Copy)]
#[repr(C)]
union C {
    _: struct {
        _: union {
            // referent field
            a: u8,

            // normal field (within the same anonymous adt)
            a: u8, //~ ERROR field `a` is already declared [E0124]
            // nested field (within the same anonymous adt)
            _: struct {
                a: u8, //~ ERROR field `a` is already declared [E0124]
            },
            // more nested field (within the same anonymous adt)
            _: union {
                _: struct {
                    a: u8, //~ ERROR field `a` is already declared [E0124]
                },
            },
            // nested field in a named adt (within the same anonymous adt)
            _: Foo, //~ ERROR field `a` is already declared
            _: Bar, //~ ERROR field `a` is already declared
            // nested field in a named adt in an anoymous adt (within the same anonymous adt)
            _: struct {
                _: Foo, //~ ERROR field `a` is already declared
                _: Bar, //~ ERROR field `a` is already declared
            },
        },

        // normal field (within the direct outer anonymous adt)
        a: u8, //~ ERROR field `a` is already declared [E0124]
        // nested field (within the direct outer anonymous adt)
        _: struct {
            a: u8, //~ ERROR field `a` is already declared [E0124]
        },
        // more nested field (within the direct outer anonymous adt)
        _: union {
            _: struct {
                a: u8, //~ ERROR field `a` is already declared [E0124]
            },
        },
        // nested field in a named adt (within the direct outer anonymous adt)
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
        // nested field in a named adt in an anoymous adt (within the direct outer anonymous adt)
        _: struct {
            _: Foo, //~ ERROR field `a` is already declared
            _: Bar, //~ ERROR field `a` is already declared
        },
    },
    // normal field
    a: u8, //~ ERROR field `a` is already declared [E0124]
    // nested field
    _: union {
        a: u8, //~ ERROR field `a` is already declared [E0124]
    },
    // more nested field
    _: struct {
        _: union {
            a: u8, //~ ERROR field `a` is already declared [E0124]
        },
    },
    // nested field in a named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: union {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a nested field in a named adt
#[derive(Clone, Copy)]
#[repr(C)]
struct D {
    // referent field `a`
    _: Foo,

    // normal field
    a: u8, //~ ERROR field `a` is already declared
    // nested field
    _: union {
        a: u8, //~ ERROR field `a` is already declared
    },
    // more nested field
    _: struct {
        _: union {
            a: u8, //~ ERROR field `a` is already declared
        },
    },
    // nested field in another named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: union {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a nested field in a nested field of a named adt
#[derive(Clone, Copy)]
#[repr(C)]
union D2 {
    // referent field `a`
    _: Bar,

    // normal field
    a: u8, //~ ERROR field `a` is already declared
    // nested field
    _: union {
        a: u8, //~ ERROR field `a` is already declared
    },
    // more nested field
    _: struct {
        _: union {
            a: u8, //~ ERROR field `a` is already declared
        },
    },
    // nested field in another named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: union {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a nested field in a named adt in an anonymous adt
#[derive(Clone, Copy)]
#[repr(C)]
struct E {
    _: struct {
        // referent field `a`
        _: Foo,

        // normal field (within the same anonymous adt)
        a: u8, //~ ERROR field `a` is already declared
        // nested field (within the same anonymous adt)
        _: struct {
            a: u8, //~ ERROR field `a` is already declared
        },
        // more nested field (within the same anonymous adt)
        _: union {
            _: struct {
                a: u8, //~ ERROR field `a` is already declared
            },
        },
        // nested field in a named adt (within the same anonymous adt)
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
        // nested field in a named adt in an anoymous adt (within the same anonymous adt)
        _: struct {
            _: Foo, //~ ERROR field `a` is already declared
            _: Bar, //~ ERROR field `a` is already declared
        },
    },

    // normal field
    a: u8, //~ ERROR field `a` is already declared
    // nested field
    _: union {
        a: u8, //~ ERROR field `a` is already declared
    },
    // more nested field
    _: struct {
        _: union {
            a: u8, //~ ERROR field `a` is already declared
        },
    },
    // nested field in another named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: union {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

// duplicated with a nested field in a named adt in an anonymous adt
#[repr(C)]
#[derive(Clone, Copy)]
union E2 {
    _: struct {
        // referent field `a`
        _: Bar,

        // normal field (within the same anonymous adt)
        a: u8, //~ ERROR field `a` is already declared
        // nested field (within the same anonymous adt)
        _: struct {
            a: u8, //~ ERROR field `a` is already declared
        },
        // more nested field (within the same anonymous adt)
        _: union {
            _: struct {
                a: u8, //~ ERROR field `a` is already declared
            },
        },
        // nested field in a named adt (within the same anonymous adt)
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
        // nested field in a named adt in an anoymous adt (within the same anonymous adt)
        _: struct {
            _: Foo, //~ ERROR field `a` is already declared
            _: Bar, //~ ERROR field `a` is already declared
        },
    },

    // normal field
    a: u8, //~ ERROR field `a` is already declared
    // nested field
    _: union {
        a: u8, //~ ERROR field `a` is already declared
    },
    // more nested field
    _: struct {
        _: union {
            a: u8, //~ ERROR field `a` is already declared
        },
    },
    // nested field in another named adt
    _: Foo, //~ ERROR field `a` is already declared
    _: Bar, //~ ERROR field `a` is already declared
    // nested field in a named adt in an anoymous adt
    _: union {
        _: Foo, //~ ERROR field `a` is already declared
        _: Bar, //~ ERROR field `a` is already declared
    },
}

fn main() {}

Version information

rustc 1.78.0-nightly (b381d3ab2 2024-02-12)
binary: rustc
commit-hash: b381d3ab27f788f990551100c4425bb782d26d76
commit-date: 2024-02-12
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 17.0.6

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

Program output

error: expected identifier, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:34:15
   |
32 |         _: union {
   |            ----- while parsing this union
33 |             
34 |               ,
   |               ^ expected identifier

error: expected `:`, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:38:18
   |
31 |     _: struct {
   |        ------ while parsing this struct
...
38 |           union  ,
   |                  ^ expected `:`

error: expected `:`, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:41:13
   |
30 | union C {
   |       - while parsing this union
...
41 |       union ,
   |             ^ expected `:`

error: expected `,`, or `}`, found `union`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:56:6
   |
56 |     }  union ,
   |      ^ help: try adding a comma: `,`

error: expected `:`, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:56:14
   |
47 | struct D {
   |        - while parsing this struct
...
56 |     }  union ,
   |              ^ expected `:`

error: expected `,`, or `}`, found `union`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:71:6
   |
71 |     }  union ,
   |      ^ help: try adding a comma: `,`

error: expected `:`, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:71:14
   |
62 | union D2 {
   |       -- while parsing this union
...
71 |     }  union ,
   |              ^ expected `:`

error: expected identifier, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:80:9
   |
78 |     _: struct {
   |        ------ while parsing this struct
79 |         
80 |         ,
   |         ^ expected identifier

error: expected `:`, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:89:13
   |
77 | struct E {
   |        - while parsing this struct
...
89 |       union ,
   |             ^ expected `:`

error: expected identifier, found `,`
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:98:9
   |
96 |     _: struct {
   |        ------ while parsing this struct
97 |         
98 |         ,
   |         ^ expected identifier

error: expected `:`, found `,`
   --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:107:13
    |
95  | union E2 {
    |       -- while parsing this union
...
107 |       union ,
    |             ^ expected `:`

error[E0412]: cannot find type `Foo` in this scope
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:49:8
   |
49 |     _: Foo,
   |        ^^^ not found in this scope

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:11:5
   |
11 |     _: union {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:11:8
   |
11 |       _: union {
   |  ________^
12 | |         a: u8,
13 | |     },
   | |_____^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:31:5
   |
31 |     _: struct {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:32:9
   |
32 |         _: union {
   |         ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:32:12
   |
32 |           _: union {
   |  ____________^
33 | |             
34 | |               ,
35 | |         },
   | |_________^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:31:8
   |
31 |       _: struct {
   |  ________^
32 | |         _: union {
33 | |             
34 | |               ,
...  |
38 | |           union  ,
39 | |     },
   | |_____^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:49:5
   |
49 |     _: Foo,
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:54:5
   |
54 |     _: union {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:54:8
   |
54 |       _: union {
   |  ________^
55 | |         a: u8, 
56 | |     }  union ,
   | |_____^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:64:5
   |
64 |     _: Bar,
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:69:5
   |
69 |     _: union {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:69:8
   |
69 |       _: union {
   |  ________^
70 | |         a: u8, 
71 | |     }  union ,
   | |_____^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:78:5
   |
78 |     _: struct {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:78:8
   |
78 |       _: struct {
   |  ________^
79 | |         
80 | |         ,
81 | |
...  |
85 | |           union  ,
86 | |     },
   | |_____^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
  --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:96:5
   |
96 |     _: struct {
   |     ^
   |
   = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
   = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
   = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0658]: unnamed fields are not yet fully implemented
   --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:96:8
    |
96  |       _: struct {
    |  ________^
97  | |         
98  | |         ,
99  | |
...   |
103 | |           union  ,
104 | |     },
    | |_____^
    |
    = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
    = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
    = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0601]: `main` function not found in crate `mvce`
   --> /tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs:108:2
    |
108 | }
    |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.dKdiA7gV4Gjk/rustc_testrunner_tmpdir_reporting.uLoaCLooipW8/mvce.rs`

thread 'rustc' panicked at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/compiler/rustc_hir/src/def.rs:647:45:
attempted .def_id() on invalid res: Err
stack backtrace:
   0:     0x7f9a1e38a476 - std::backtrace_rs::backtrace::libunwind::trace::h3f288a3148e8bb15
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7f9a1e38a476 - std::backtrace_rs::backtrace::trace_unsynchronized::h7277353061928bc0
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7f9a1e38a476 - std::sys_common::backtrace::_print_fmt::hbf79f06a8c92ca0e
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7f9a1e38a476 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h0afd1ff8e38a8a84
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7f9a1e3dd030 - core::fmt::rt::Argument::fmt::h7f26a9b6a6522b09
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/fmt/rt.rs:142:9
   5:     0x7f9a1e3dd030 - core::fmt::write::he7de9de816f98016
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/fmt/mod.rs:1120:17
   6:     0x7f9a1e37dc6f - std::io::Write::write_fmt::h38e65bf4265dc66c
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/io/mod.rs:1854:15
   7:     0x7f9a1e38a254 - std::sys_common::backtrace::_print::hf1424a842a74edeb
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7f9a1e38a254 - std::sys_common::backtrace::print::hbb43acdb160822bd
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7f9a1e38d047 - std::panicking::default_hook::{{closure}}::h9c602a562527e529
  10:     0x7f9a1e38cda9 - std::panicking::default_hook::h9cb3bf5f6c73326f
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:292:9
  11:     0x7f9a2115cfdc - std[73253c920228642]::panicking::update_hook::<alloc[940273873142bb35]::boxed::Box<rustc_driver_impl[f037f419b039420a]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7f9a1e38d796 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h1e0fe9ec90d27cc3
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2030:9
  13:     0x7f9a1e38d796 - std::panicking::rust_panic_with_hook::hb5ad56797fd964c4
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:785:13
  14:     0x7f9a1e38d4e2 - std::panicking::begin_panic_handler::{{closure}}::hd364aeee29433213
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:659:13
  15:     0x7f9a1e38a976 - std::sys_common::backtrace::__rust_end_short_backtrace::ha10bb1568b9ec73d
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7f9a1e38d234 - rust_begin_unwind
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:647:5
  17:     0x7f9a1e3d9785 - core::panicking::panic_fmt::h91fa7152f33c7717
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/panicking.rs:72:14
  18:     0x7f9a2123fdb3 - <rustc_hir[6019942fb8e590f1]::def::Res>::def_id
  19:     0x7f9a238aa75c - <rustc_hir_analysis[9a410817be2ff534]::collect::FieldUniquenessCheckContext>::check_field.cold.0
  20:     0x7f9a23042a54 - rustc_hir_analysis[9a410817be2ff534]::collect::convert_variant
  21:     0x7f9a23042363 - rustc_hir_analysis[9a410817be2ff534]::collect::adt_def
  22:     0x7f9a2247aa15 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::adt_def::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>
  23:     0x7f9a2247b0e1 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  24:     0x7f9a2247a3de - rustc_query_impl[b78e7f0549dc02d3]::query_impl::adt_def::get_query_non_incr::__rust_end_short_backtrace
  25:     0x7f9a226e7cd7 - rustc_middle[dbb6cff8550fbced]::query::plumbing::query_get_at::<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>>
  26:     0x7f9a22963560 - rustc_hir_analysis[9a410817be2ff534]::outlives::inferred_outlives_crate
  27:     0x7f9a22962420 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::inferred_outlives_crate::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>
  28:     0x7f9a231fc34e - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::SingleCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  29:     0x7f9a231fce46 - rustc_query_impl[b78e7f0549dc02d3]::query_impl::inferred_outlives_crate::get_query_non_incr::__rust_end_short_backtrace
  30:     0x7f9a22964bf5 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::inferred_outlives_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 16usize]>>
  31:     0x7f9a22518503 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 16usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  32:     0x7f9a22517eea - rustc_query_impl[b78e7f0549dc02d3]::query_impl::inferred_outlives_of::get_query_non_incr::__rust_end_short_backtrace
  33:     0x7f9a22563e22 - rustc_hir_analysis[9a410817be2ff534]::collect::predicates_defined_on
  34:     0x7f9a22563c53 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::predicates_defined_on::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 24usize]>>
  35:     0x7f9a22564de7 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  36:     0x7f9a22564920 - rustc_query_impl[b78e7f0549dc02d3]::query_impl::predicates_defined_on::get_query_non_incr::__rust_end_short_backtrace
  37:     0x7f9a22566595 - rustc_hir_analysis[9a410817be2ff534]::collect::predicates_of::predicates_of
  38:     0x7f9a22566493 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::predicates_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 24usize]>>
  39:     0x7f9a22564e14 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 24usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  40:     0x7f9a225649fe - rustc_query_impl[b78e7f0549dc02d3]::query_impl::predicates_of::get_query_non_incr::__rust_end_short_backtrace
  41:     0x7f9a227a2970 - <rustc_hir_analysis[9a410817be2ff534]::collect::CollectItemTypesVisitor as rustc_hir[6019942fb8e590f1]::intravisit::Visitor>::visit_item
  42:     0x7f9a227a18c8 - rustc_hir_analysis[9a410817be2ff534]::collect::collect_mod_item_types
  43:     0x7f9a227a185b - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::collect_mod_item_types::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 0usize]>>
  44:     0x7f9a22ef2d3b - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefaultCache<rustc_span[a4806a91d128f927]::def_id::LocalModDefId, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  45:     0x7f9a22ef285f - rustc_query_impl[b78e7f0549dc02d3]::query_impl::collect_mod_item_types::get_query_non_incr::__rust_end_short_backtrace
  46:     0x7f9a2256e30e - rustc_hir_analysis[9a410817be2ff534]::check_crate
  47:     0x7f9a22de0419 - rustc_interface[ceb207a8fb5539d]::passes::analysis
  48:     0x7f9a22de005f - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 1usize]>>
  49:     0x7f9a232c6064 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::SingleCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  50:     0x7f9a232c5dc7 - rustc_query_impl[b78e7f0549dc02d3]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  51:     0x7f9a231409fb - rustc_interface[ceb207a8fb5539d]::interface::run_compiler::<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}
  52:     0x7f9a2336ef12 - std[73253c920228642]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_with_globals<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_pool_with_globals<rustc_interface[ceb207a8fb5539d]::interface::run_compiler<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>
  53:     0x7f9a2336ed3e - <<std[73253c920228642]::thread::Builder>::spawn_unchecked_<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_with_globals<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_pool_with_globals<rustc_interface[ceb207a8fb5539d]::interface::run_compiler<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#1} as core[ed182bbac36ed604]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  54:     0x7f9a1e396985 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h37d86e7af57ec8cf
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2016:9
  55:     0x7f9a1e396985 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h99a2218ed45ac1ce
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2016:9
  56:     0x7f9a1e396985 - std::sys::pal::unix::thread::Thread::new::thread_start::h6344e9d30547345d
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys/pal/unix/thread.rs:108:17
  57:     0x7f9a1e17b9eb - <unknown>
  58:     0x7f9a1e1ff7cc - <unknown>
  59:                0x0 - <unknown>

error: the compiler unexpectedly panicked. this is a bug.

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 1.78.0-nightly (b381d3ab2 2024-02-12) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [adt_def] computing ADT definition for `D`
#1 [inferred_outlives_crate] computing the inferred outlives predicates for items in this crate
#2 [inferred_outlives_of] computing inferred outlives predicates of `Bar`
#3 [predicates_defined_on] computing predicates of `Bar`
#4 [predicates_of] computing predicates of `Bar`
#5 [collect_mod_item_types] collecting item types in top-level module
#6 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 29 previous errors

Some errors have detailed explanations: E0412, E0601, E0658.
For more information about an error, try `rustc --explain E0412`.

[matthiaskrgr]

#![feature(unnamed_fields)]
#[repr(C)]
struct D {
    _: Foo,
    _: union {
    }
}

pub fn main() {}

#115367

[fmease]

Lol, what's up with all the unnecessary whitespace in your treereduce reproducers? Could you teach treereduce to reduce that? :P

[fmease]

Also I would probably place the MCVE from #120992 (comment) into the issue description and the original reproducer inside a <details /> (or omit it entirely) since this GitHub issue is super hard to read imo

[matthiaskrgr]

auto-reduced (treereduce-rust):

struct TypedArenaChunk {
    next: Optionlet _: usize = ()
    
    
    
}

original:

struct TypedArenaChunk {
    next: Optionlet _: usize = ()
    //~^ ERROR mismatched types
    //~| ERROR expected `;`String>>
    //~^ ERROR unmatched angle bracket
}

fn main() {}

Version information

rustc 1.78.0-nightly (b381d3ab2 2024-02-12)
binary: rustc
commit-hash: b381d3ab27f788f990551100c4425bb782d26d76
commit-date: 2024-02-12
host: x86_64-unknown-linux-gnu
release: 1.78.0-nightly
LLVM version: 17.0.6

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

Program output

error: expected `,`, or `}`, found reserved identifier `_`
 --> /tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs:2:20
  |
2 |     next: Optionlet _: usize = ()
  |                    ^ help: try adding a comma: `,`

error: default values on `struct` fields aren't supported
 --> /tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs:2:29
  |
2 |     next: Optionlet _: usize = ()
  |                             ^^^^^ help: remove this unsupported default value

error[E0412]: cannot find type `Optionlet` in this scope
   --> /tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs:2:11
    |
2   |     next: Optionlet _: usize = ()
    |           ^^^^^^^^^ help: an enum with a similar name exists: `Option`
    |
   ::: /home/matthias/.rustup/toolchains/master/lib/rustlib/src/rust/library/core/src/option.rs:571:1
    |
571 | pub enum Option<T> {
    | ------------------ similarly named enum `Option` defined here

error[E0658]: unnamed fields are not yet fully implemented
 --> /tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs:2:21
  |
2 |     next: Optionlet _: usize = ()
  |                     ^
  |
  = note: see issue #49804 <https://github.com/rust-lang/rust/issues/49804> for more information
  = help: add `#![feature(unnamed_fields)]` to the crate attributes to enable
  = note: this compiler was built on 2024-02-12; consider upgrading it if it is out of date

error[E0601]: `main` function not found in crate `mvce`
 --> /tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs:6:2
  |
6 | }
  |  ^ consider adding a `main` function to `/tmp/icemaker_global_tempdir.BqZKfZYQSE4S/rustc_testrunner_tmpdir_reporting.a3eGjPeXLcM9/mvce.rs`

thread 'rustc' panicked at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/compiler/rustc_hir/src/def.rs:647:45:
attempted .def_id() on invalid res: PrimTy(Uint(Usize))
stack backtrace:
   0:     0x7fc25db8a476 - std::backtrace_rs::backtrace::libunwind::trace::h3f288a3148e8bb15
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/../../backtrace/src/backtrace/libunwind.rs:104:5
   1:     0x7fc25db8a476 - std::backtrace_rs::backtrace::trace_unsynchronized::h7277353061928bc0
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/../../backtrace/src/backtrace/mod.rs:66:5
   2:     0x7fc25db8a476 - std::sys_common::backtrace::_print_fmt::hbf79f06a8c92ca0e
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:68:5
   3:     0x7fc25db8a476 - <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt::h0afd1ff8e38a8a84
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:44:22
   4:     0x7fc25dbdd030 - core::fmt::rt::Argument::fmt::h7f26a9b6a6522b09
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/fmt/rt.rs:142:9
   5:     0x7fc25dbdd030 - core::fmt::write::he7de9de816f98016
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/fmt/mod.rs:1120:17
   6:     0x7fc25db7dc6f - std::io::Write::write_fmt::h38e65bf4265dc66c
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/io/mod.rs:1854:15
   7:     0x7fc25db8a254 - std::sys_common::backtrace::_print::hf1424a842a74edeb
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:47:5
   8:     0x7fc25db8a254 - std::sys_common::backtrace::print::hbb43acdb160822bd
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:34:9
   9:     0x7fc25db8d047 - std::panicking::default_hook::{{closure}}::h9c602a562527e529
  10:     0x7fc25db8cda9 - std::panicking::default_hook::h9cb3bf5f6c73326f
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:292:9
  11:     0x7fc26095cfdc - std[73253c920228642]::panicking::update_hook::<alloc[940273873142bb35]::boxed::Box<rustc_driver_impl[f037f419b039420a]::install_ice_hook::{closure#0}>>::{closure#0}
  12:     0x7fc25db8d796 - <alloc::boxed::Box<F,A> as core::ops::function::Fn<Args>>::call::h1e0fe9ec90d27cc3
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2030:9
  13:     0x7fc25db8d796 - std::panicking::rust_panic_with_hook::hb5ad56797fd964c4
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:785:13
  14:     0x7fc25db8d4e2 - std::panicking::begin_panic_handler::{{closure}}::hd364aeee29433213
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:659:13
  15:     0x7fc25db8a976 - std::sys_common::backtrace::__rust_end_short_backtrace::ha10bb1568b9ec73d
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys_common/backtrace.rs:171:18
  16:     0x7fc25db8d234 - rust_begin_unwind
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/panicking.rs:647:5
  17:     0x7fc25dbd9785 - core::panicking::panic_fmt::h91fa7152f33c7717
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/core/src/panicking.rs:72:14
  18:     0x7fc260a3fdb3 - <rustc_hir[6019942fb8e590f1]::def::Res>::def_id
  19:     0x7fc2630aa75c - <rustc_hir_analysis[9a410817be2ff534]::collect::FieldUniquenessCheckContext>::check_field.cold.0
  20:     0x7fc262842bb8 - rustc_hir_analysis[9a410817be2ff534]::collect::convert_variant
  21:     0x7fc262842363 - rustc_hir_analysis[9a410817be2ff534]::collect::adt_def
  22:     0x7fc261c7aa15 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::adt_def::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>
  23:     0x7fc261c7b0e1 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  24:     0x7fc261c7a3de - rustc_query_impl[b78e7f0549dc02d3]::query_impl::adt_def::get_query_non_incr::__rust_end_short_backtrace
  25:     0x7fc261ee7cd7 - rustc_middle[dbb6cff8550fbced]::query::plumbing::query_get_at::<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>>
  26:     0x7fc25fec1bf2 - rustc_hir_analysis[9a410817be2ff534]::collect::type_of::type_of
  27:     0x7fc261c7c466 - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::type_of::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>
  28:     0x7fc261c7b0e1 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefIdCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 8usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  29:     0x7fc261c7abdd - rustc_query_impl[b78e7f0549dc02d3]::query_impl::type_of::get_query_non_incr::__rust_end_short_backtrace
  30:     0x7fc261fa28e6 - <rustc_hir_analysis[9a410817be2ff534]::collect::CollectItemTypesVisitor as rustc_hir[6019942fb8e590f1]::intravisit::Visitor>::visit_item
  31:     0x7fc261fa18c8 - rustc_hir_analysis[9a410817be2ff534]::collect::collect_mod_item_types
  32:     0x7fc261fa185b - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::collect_mod_item_types::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 0usize]>>
  33:     0x7fc2626f2d3b - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::DefaultCache<rustc_span[a4806a91d128f927]::def_id::LocalModDefId, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 0usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  34:     0x7fc2626f285f - rustc_query_impl[b78e7f0549dc02d3]::query_impl::collect_mod_item_types::get_query_non_incr::__rust_end_short_backtrace
  35:     0x7fc261d6e30e - rustc_hir_analysis[9a410817be2ff534]::check_crate
  36:     0x7fc2625e0419 - rustc_interface[ceb207a8fb5539d]::passes::analysis
  37:     0x7fc2625e005f - rustc_query_impl[b78e7f0549dc02d3]::plumbing::__rust_begin_short_backtrace::<rustc_query_impl[b78e7f0549dc02d3]::query_impl::analysis::dynamic_query::{closure#2}::{closure#0}, rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 1usize]>>
  38:     0x7fc262ac6064 - rustc_query_system[74854bfa6cddafab]::query::plumbing::try_execute_query::<rustc_query_impl[b78e7f0549dc02d3]::DynamicConfig<rustc_query_system[74854bfa6cddafab]::query::caches::SingleCache<rustc_middle[dbb6cff8550fbced]::query::erase::Erased<[u8; 1usize]>>, false, false, false>, rustc_query_impl[b78e7f0549dc02d3]::plumbing::QueryCtxt, false>
  39:     0x7fc262ac5dc7 - rustc_query_impl[b78e7f0549dc02d3]::query_impl::analysis::get_query_non_incr::__rust_end_short_backtrace
  40:     0x7fc2629409fb - rustc_interface[ceb207a8fb5539d]::interface::run_compiler::<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}
  41:     0x7fc262b6ef12 - std[73253c920228642]::sys_common::backtrace::__rust_begin_short_backtrace::<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_with_globals<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_pool_with_globals<rustc_interface[ceb207a8fb5539d]::interface::run_compiler<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>
  42:     0x7fc262b6ed3e - <<std[73253c920228642]::thread::Builder>::spawn_unchecked_<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_with_globals<rustc_interface[ceb207a8fb5539d]::util::run_in_thread_pool_with_globals<rustc_interface[ceb207a8fb5539d]::interface::run_compiler<core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>, rustc_driver_impl[f037f419b039420a]::run_compiler::{closure#0}>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#0}::{closure#0}, core[ed182bbac36ed604]::result::Result<(), rustc_span[a4806a91d128f927]::ErrorGuaranteed>>::{closure#1} as core[ed182bbac36ed604]::ops::function::FnOnce<()>>::call_once::{shim:vtable#0}
  43:     0x7fc25db96985 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h37d86e7af57ec8cf
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2016:9
  44:     0x7fc25db96985 - <alloc::boxed::Box<F,A> as core::ops::function::FnOnce<Args>>::call_once::h99a2218ed45ac1ce
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/alloc/src/boxed.rs:2016:9
  45:     0x7fc25db96985 - std::sys::pal::unix::thread::Thread::new::thread_start::h6344e9d30547345d
                               at /rustc/b381d3ab27f788f990551100c4425bb782d26d76/library/std/src/sys/pal/unix/thread.rs:108:17
  46:     0x7fc25d9809eb - <unknown>
  47:     0x7fc25da047cc - <unknown>
  48:                0x0 - <unknown>

error: the compiler unexpectedly panicked. this is a bug.

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 1.78.0-nightly (b381d3ab2 2024-02-12) running on x86_64-unknown-linux-gnu

query stack during panic:
#0 [adt_def] computing ADT definition for `TypedArenaChunk`
#1 [type_of] computing type of `TypedArenaChunk`
#2 [collect_mod_item_types] collecting item types in top-level module
#3 [analysis] running analysis passes on this crate
end of query stack
error: aborting due to 5 previous errors

Some errors have detailed explanations: E0412, E0601, E0658.
For more information about an error, try `rustc --explain E0412`.

[matthiaskrgr]

@fmease im actually running rustfmt after reducing before generating the report, but treereduce sometimes slighlty misreduces the code (e.g. fn a(a: i32, b: i32, c:i32) to fn a(, , c: i32 or sth, so that rustfmt bails out due to syntax error and no longer squashes empty lines :/
Also likely to encounter code that rustfmt does not know about yet, sometimes it also just removes the part that would ICE lol.

I can see if I can add some kind of self-coded cleanup after rustfmt even.

[matthiaskrgr]

Right now the report is generated fully automatic, the "reduced" mvce is never put into details, the original one only if its bigger than X lines, also the program output should match the mvce imo, mmh

[clubby789]

All of the examples in here no longer ICE so I'm pretty sure #121198 got this too