Auto merge of #136389 - matthiaskrgr:rollup-x453dy9, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #130514 (Implement MIR lowering for unsafe binders)
 - #135684 (docs: Documented Send and Sync requirements for Mutex + MutexGuard)
 - #136307 (Implement all mix/max functions in a (hopefully) more optimization amendable way)
 - #136360 (Stabilize `once_wait`)
 - #136364 (document that ptr cmp is unsigned)
 - #136374 (Add link attribute for Enzyme's LLVMRust FFI)

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

2 files changed, 8 insertions, 0 deletions

diff --git a/compiler/rustc_const_eval/src/interpret/projection.rs b/compiler/rustc_const_eval/src/interpret/projection.rs
index 996142d7b03..8ecb3e13d5c 100644
--- a/compiler/rustc_const_eval/src/interpret/projection.rs
+++ b/compiler/rustc_const_eval/src/interpret/projection.rs
@@ -381,6 +381,7 @@ where
             OpaqueCast(ty) => {
                 span_bug!(self.cur_span(), "OpaqueCast({ty}) encountered after borrowck")
             }
+            UnwrapUnsafeBinder(target) => base.transmute(self.layout_of(target)?, self)?,
             // We don't want anything happening here, this is here as a dummy.
             Subtype(_) => base.transmute(base.layout(), self)?,
             Field(field, _) => self.project_field(base, field.index())?,
diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs
index d9c0ff5acd1..abe73c43d8a 100644
--- a/compiler/rustc_const_eval/src/interpret/step.rs
+++ b/compiler/rustc_const_eval/src/interpret/step.rs
@@ -277,6 +277,13 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
                 let discr = self.discriminant_for_variant(op.layout.ty, variant)?;
                 self.write_immediate(*discr, &dest)?;
             }
+
+            WrapUnsafeBinder(ref op, _ty) => {
+                // Constructing an unsafe binder acts like a transmute
+                // since the operand's layout does not change.
+                let op = self.eval_operand(op, None)?;
+                self.copy_op_allow_transmute(&op, &dest)?;
+            }
         }
 
         trace!("{:?}", self.dump_place(&dest));