Auto merge of #121804 - GuillaumeGomez:rollup-jh0v3ex, r=GuillaumeGomez

Rollup of 7 pull requests

Successful merges:

 - #119748 (Increase visibility of `join_path` and `split_paths`)
 - #120820 (Enable CMPXCHG16B, SSE3, SAHF/LAHF and 128-bit Atomics (in nightly) in Windows x64)
 - #121000 (pattern_analysis: rework how we hide empty private fields)
 - #121376 (Skip unnecessary comparison with half-open range patterns)
 - #121596 (Use volatile access instead of `#[used]` for `on_tls_callback`)
 - #121669 (Count stashed errors again)
 - #121783 (Emitter cleanups)

r? `@ghost`
`@rustbot` modify labels: rollup

1 files changed, 7 insertions, 3 deletions

diff --git a/compiler/rustc_pattern_analysis/src/lib.rs b/compiler/rustc_pattern_analysis/src/lib.rs
index 164dc36b679..d4b38d260e7 100644
--- a/compiler/rustc_pattern_analysis/src/lib.rs
+++ b/compiler/rustc_pattern_analysis/src/lib.rs
@@ -82,6 +82,11 @@ use crate::usefulness::{compute_match_usefulness, ValidityConstraint};
 pub trait Captures<'a> {}
 impl<'a, T: ?Sized> Captures<'a> for T {}
 
+/// `bool` newtype that indicates whether this is a privately uninhabited field that we should skip
+/// during analysis.
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
+pub struct PrivateUninhabitedField(pub bool);
+
 /// Context that provides type information about constructors.
 ///
 /// Most of the crate is parameterized on a type that implements this trait.
@@ -105,13 +110,12 @@ pub trait TypeCx: Sized + fmt::Debug {
     /// The number of fields for this constructor.
     fn ctor_arity(&self, ctor: &Constructor<Self>, ty: &Self::Ty) -> usize;
 
-    /// The types of the fields for this constructor. The result must have a length of
-    /// `ctor_arity()`.
+    /// The types of the fields for this constructor. The result must contain `ctor_arity()` fields.
     fn ctor_sub_tys<'a>(
         &'a self,
         ctor: &'a Constructor<Self>,
         ty: &'a Self::Ty,
-    ) -> impl Iterator<Item = Self::Ty> + ExactSizeIterator + Captures<'a>;
+    ) -> impl Iterator<Item = (Self::Ty, PrivateUninhabitedField)> + ExactSizeIterator + Captures<'a>;
 
     /// The set of all the constructors for `ty`.
     ///