Merge ref '873d4682c7d2' from rust-lang/rust

Pull recent changes from https://github.com/rust-lang/rust via Josh.

Upstream ref: rust-lang/rust@873d468
Filtered ref: 003d326
Upstream diff: rust-lang/rust@4862272...873d468

This merge was created using https://github.com/rust-lang/josh-sync.

Author: The rustc-josh-sync Cronjob Bot

crates/core_arch/src/arm_shared/hints.rs

@@ -83,8 +83,11 @@ pub unsafe fn __sevl() {
 /// improve overall system performance.
 // Section 10.1 of ACLE says that the supported arches are: 8, 6K, 6-M
 // LLVM says "instruction requires: armv6k"
+// On ARMv6 in Thumb mode, T2 is required (see Arm DDI0406C Section A8.8.427)
 #[cfg(any(
-    target_feature = "v6",
+    all(target_feature = "v6k", not(target_feature = "thumb-mode")),
+    target_feature = "v6t2",
+    all(target_feature = "v6", target_feature = "mclass"),
     target_arch = "aarch64",
     target_arch = "arm64ec",
     doc