Auto merge of #147284 - cuviper:beta-next, r=cuviper

[beta] backports

- remove incorrect fast path #146919
- Update LLVM to 21.1.2 #146953
- Fix infinite recursion in Path::eq with String #146958

r? cuviper

Author: bors

compiler/rustc_trait_selection/src/infer.rs

@@ -9,7 +9,7 @@ use rustc_middle::infer::canonical::{
     Canonical, CanonicalQueryInput, CanonicalQueryResponse, QueryResponse,
 };
 use rustc_middle::traits::query::NoSolution;
-use rustc_middle::ty::{self, GenericArg, Ty, TyCtxt, TypeFoldable, TypeVisitableExt, Upcast};
+use rustc_middle::ty::{self, GenericArg, Ty, TyCtxt, TypeFoldable, Upcast};
 use rustc_span::DUMMY_SP;
 use tracing::instrument;
 
@@ -31,19 +31,7 @@ impl<'tcx> InferCtxt<'tcx> {
 
     fn type_is_copy_modulo_regions(&self, param_env: ty::ParamEnv<'tcx>, ty: Ty<'tcx>) -> bool {
         let ty = self.resolve_vars_if_possible(ty);
-
-        // FIXME(#132279): This should be removed as it causes us to incorrectly
-        // handle opaques in their defining scope, and stalled coroutines.
-        if !self.next_trait_solver() && !(param_env, ty).has_infer() && !ty.has_coroutines() {
-            return self.tcx.type_is_copy_modulo_regions(self.typing_env(param_env), ty);
-        }
-
         let copy_def_id = self.tcx.require_lang_item(LangItem::Copy, DUMMY_SP);
-
-        // This can get called from typeck (by euv), and `moves_by_default`
-        // rightly refuses to work with inference variables, but
-        // moves_by_default has a cache, which we want to use in other
-        // cases.
         traits::type_known_to_meet_bound_modulo_regions(self, param_env, ty, copy_def_id)
     }
 

library/std/src/path.rs

@@ -2107,31 +2107,31 @@ impl PartialEq for PathBuf {
 impl cmp::PartialEq<str> for PathBuf {
     #[inline]
     fn eq(&self, other: &str) -> bool {
-        Path::eq(self, other)
+        self.as_path() == other
     }
 }
 
 #[stable(feature = "eq_str_for_path", since = "1.91.0")]
 impl cmp::PartialEq<PathBuf> for str {
     #[inline]
     fn eq(&self, other: &PathBuf) -> bool {
-        other == self
+        self == other.as_path()
     }
 }
 
 #[stable(feature = "eq_str_for_path", since = "1.91.0")]
 impl cmp::PartialEq<String> for PathBuf {
     #[inline]
     fn eq(&self, other: &String) -> bool {
-        **self == **other
+        self.as_path() == other.as_str()
     }
 }
 
 #[stable(feature = "eq_str_for_path", since = "1.91.0")]
 impl cmp::PartialEq<PathBuf> for String {
     #[inline]
     fn eq(&self, other: &PathBuf) -> bool {
-        other == self
+        self.as_str() == other.as_path()
     }
 }
 
@@ -3426,15 +3426,15 @@ impl cmp::PartialEq<Path> for str {
 impl cmp::PartialEq<String> for Path {
     #[inline]
     fn eq(&self, other: &String) -> bool {
-        self == &*other
+        self == other.as_str()
     }
 }
 
 #[stable(feature = "eq_str_for_path", since = "1.91.0")]
 impl cmp::PartialEq<Path> for String {
     #[inline]
     fn eq(&self, other: &Path) -> bool {
-        other == self
+        self.as_str() == other
     }
 }
 

library/std/tests/path.rs

@@ -2528,7 +2528,17 @@ fn normalize_lexically() {
 }
 
 #[test]
-/// See issue#146183
-fn compare_path_to_str() {
-    assert!(&PathBuf::from("x") == "x");
+/// See issue#146183 and issue#146940
+fn compare_path_like_to_str_like() {
+    let path_buf = PathBuf::from("x");
+    let path = Path::new("x");
+    let s = String::from("x");
+    assert!(path == "x");
+    assert!("x" == path);
+    assert!(path == &s);
+    assert!(&s == path);
+    assert!(&path_buf == "x");
+    assert!("x" == &path_buf);
+    assert!(path_buf == s);
+    assert!(s == path_buf);
 }

src/llvm-project

@@ -0,0 +1,40 @@
+//@ edition: 2024
+//@ revisions: current next
+//@[next] compile-flags: -Znext-solver
+//@ check-pass
+
+// Regression test for #146813. We previously used a pseudo-canonical
+// query during HIR typeck which caused a query cycle when looking at the
+// witness of a coroutine.
+
+use std::future::Future;
+
+trait ConnectMiddleware {}
+
+trait ConnectHandler: Sized {
+    fn with<M>(self, _: M) -> impl ConnectHandler
+    where
+        M: ConnectMiddleware,
+    {
+        LayeredConnectHandler
+    }
+}
+
+struct LayeredConnectHandler;
+impl ConnectHandler for LayeredConnectHandler {}
+impl<F> ConnectHandler for F where F: FnOnce() {}
+
+impl<F, Fut> ConnectMiddleware for F
+where
+    F: FnOnce() -> Fut,
+    Fut: Future<Output = ()> + Send,
+{
+}
+
+pub async fn fails() {
+    { || {} }
+        .with(async || ())
+        .with(async || ())
+        .with(async || ());
+}
+fn main() {}