Regression: Typemap type mismatch in 1.34.0+ #60375
Comments
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Ping: @dpc |
Would it be possible to paste the runtime error? |
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@IslandUsurper Did you want to ping the other dpc? 😄 |
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cc @Dylan-DPC ^--- |
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Same problem while running the example in README of natice-windows-gui . OS : Windows 10 2016 ltsb (version 1607) The last frame in main is 12 , a nwg_get! macro call, defined as /**
Return controls from the Ui. Panics if one of the controls could not be retrieved.
To avoid the panic, use `ui.get` directly.
Usage:
`let control = nwg_get!(ui; (control ID, control type))`
`let (control1, control2) = nwg_get!(ui; [(control1_ID, control1 type), (control2_ID, control2_type)])`
*/
#[macro_export]
macro_rules! nwg_get {
( $ui:ident; ($n:expr, $t:ty) ) => {
$ui.get::<$t>(&$n).expect("Failed to find a control")
};
( $ui:ident; [ $( ($n:expr, $t:ty) ),* ] ) => {
(
$( $ui.get::<$t>(&$n).expect("Failed to find a control") ),*
)
}
} |
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triage: Not quite clear on what is going on here; maybe something with using |
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It seems like what is really needed here is to try and narrow this to a standalone test case that is not reliant on |
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triage: P-high Behavorial regression, unknown cause, needs help to track down the problem. |
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Hey this is my project. I'll try to isolate the problem to make it a bit easier to fix... hopefully. |
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Ok I think I've found something. Hopefully it makes sense. It seems like there are two methods named "type_id" (one from For example, this code does not compile: use std::any::Any;
use std::any::TypeId;
trait Resource {
}
trait ResourceT {
fn type_id(&self) -> TypeId;
}
struct TestResourceT {
value: u32
}
impl ResourceT for TestResourceT {
fn type_id(&self) -> TypeId { TypeId::of::<TestResource>() }
}
struct TestResource {}
fn main() {
let test = TestResourceT{ value: 10 };
println!("{:?}", TypeId::of::<TestResource>());
println!("{:?}", test.type_id());
}The compiler will output That said, if you remove Here's a snippet that run the bogus code from native-windows-gui: https://gist.github.com/gabdube/ef27e073c209b23b06d794dca9982af2 Again, removing |
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Triage: latest example still reproduces |
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I reduced the failing test case: // This program compiles but asserts when std::any::Any is in scope,
// but compiles and runs successfully when it is not in scope.
use std::any::Any;
use std::any::TypeId;
trait Resource {
fn type_id(&self) -> TypeId;
}
impl Resource for () {
fn type_id(&self) -> TypeId { TypeId::of::<()>() }
}
fn main() {
let tid_orig = TypeId::of::<()>();
let ref_res: &dyn Resource = &();
let tid_from_ref = ref_res.type_id();
let box_res: Box<dyn Resource> = Box::new(());
let tid_from_box = box_res.type_id();
dbg!(tid_orig, tid_from_ref, tid_from_box);
assert_eq!(tid_orig, tid_from_ref); // passes
assert_eq!(tid_orig, tid_from_box); // fails
}Take note of the asserts; the failure only happens on boxed trait objects. It took me a while to realize that So I don't think there's any action to be taken here. The behavior here is a consequence of trait objects, autoderef, and a blanket impl. 1.34 just happened to be the release when |
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We reviewed this in today's @rust-lang/libs meeting. Sorry that this took so long for us to get to! This kind of issue is why we don't normally implement methods on |
I first reported this issue at gabdube/native-windows-gui#69, but discussion on Discord led me to file an issue here.
native-windows-ui stores data about the application (form controls, state, etc.) through a typemap. While my program worked on Rust 1.32.0 and 1.33.0, it breaks on 1.34.0 and 1.34.1. Sadly, this is a runtime error, and no backtrace is generated even with the RUST_BACKTRACE flag.
The error that is generated is
native_windows_gui::Error::BadType.The text was updated successfully, but these errors were encountered: