Hang: Compiler hang in resolving Matrix<(), > with GATs [next-solver]

I tried this code:（auto-reduce）

trait HasAlias {}
struct Dummy;
trait DummyTrait {
    type DummyType<T>;
}
impl DummyTrait for Dummy {
    type DummyType<T> = T;
}
type AliasOf<T> = <Dummy as DummyTrait>::DummyType<T>;
struct Matrix<T, S>(T, S);
type OMatrix<T> = Matrix<T, AliasOf<T>>;

trait SimdValue {
    type Element;
}
impl<T: HasAlias + SimdValue> SimdValue for OMatrix<T> {
    type Element = OMatrix<T::Element>;
}
trait Unimplemented {}
trait MyFrom<T> {}
impl<T> MyFrom<T> for T {}
impl<T: SimdValue> MyFrom<T> for OMatrix<T::Element> {}
impl<T, S> HasAlias for Matrix<T, S> {}
impl Unimplemented for Matrix<()> {}
fn main() {}

The compiler hangs even with -Z next-solver=globally

Meta

rustc --version --verbose:

rustc 1.95.0-nightly (eda76d9d1 2026-01-21)
binary: rustc
commit-hash: eda76d9d1d133effbf7facb28168fd78d75fd434
commit-date: 2026-01-21
host: x86_64-unknown-linux-gnu
release: 1.95.0-nightly
LLVM version: 21.1.8

Hangs.

Start by compiling the reduced Rust example and compare the default solver with -Znext-solver=globally, confirming the hang on the reported nightly version. Trace the compiler's trait-solving path for the GAT alias, overlapping MyFrom implementations, and Matrix bounds; done means the reproducer terminates without introducing incorrect diagnostics.