Closed
Description
trait Trait {
type Assoc;
}
struct Foo<T, U>(T)
where
T: Trait<Assoc = U>;
impl Trait for for<'a> fn(&'a ()) {
type Assoc = u32;
}
impl Trait for fn(&'static ()) {
type Assoc = String;
}
fn foo(x: Foo<for<'a> fn(&'a ()), u32>) -> Foo<fn(&'static ()), String> {
x
}
fn main() {}
results in the following ICE:
error: internal compiler error: broken MIR in DefId(0:15 ~ example[9884]::foo) (_0 = move _1): bad assignment (Foo<fn(&()), std::string::String> = Foo<for<'a> fn(&'a ()), u32>): NoSolution
--> <source>:17:5
|
17 | x
| ^
thread 'rustc' panicked at 'aborting due to `-Z treat-err-as-bug=1`', compiler/rustc_errors/src/lib.rs:1561:30
stack backtrace:
----------- SNIP ----------------------
17: 0x7fe0e8c751b3 - <rustc_errors[1020869c0a53ac34]::HandlerInner>::panic_if_treat_err_as_bug
18: 0x7fe0e8c73258 - <rustc_errors[1020869c0a53ac34]::HandlerInner>::emit_diagnostic
19: 0x7fe0ea774481 - <rustc_errors[1020869c0a53ac34]::HandlerInner>::emit_diag_at_span::<rustc_span[efd8b0f1895919e0]::span_encoding::Span>
20: 0x7fe0ea774603 - <rustc_errors[1020869c0a53ac34]::HandlerInner>::span_bug::<rustc_span[efd8b0f1895919e0]::span_encoding::Span, &str>
21: 0x7fe0ea773c55 - <rustc_errors[1020869c0a53ac34]::Handler>::delay_span_bug::<rustc_span[efd8b0f1895919e0]::span_encoding::Span, &str>
22: 0x7fe0e9228157 - <rustc_borrowck[e2ad9be94bf77b7a]::type_check::TypeChecker>::typeck_mir
23: 0x7fe0e919c351 - rustc_borrowck[e2ad9be94bf77b7a]::type_check::type_check
24: 0x7fe0e9187179 - rustc_borrowck[e2ad9be94bf77b7a]::nll::compute_regions
25: 0x7fe0e915c6e8 - rustc_borrowck[e2ad9be94bf77b7a]::do_mir_borrowck
26: 0x7fe0e9b8f296 - rustc_borrowck[e2ad9be94bf77b7a]::mir_borrowck
This should compile