3 files changed, 18 insertions, 13 deletions
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index 297b2fa143d..a0851aa557b 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -726,7 +726,7 @@ fn replace_resume_ty_local<'tcx>(
 /// The async lowering step and the type / lifetime inference / checking are
 /// still using the `resume` argument for the time being. After this transform,
 /// the coroutine body doesn't have the `resume` argument.
-fn transform_gen_context<'tcx>(_tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+fn transform_gen_context<'tcx>(body: &mut Body<'tcx>) {
     // This leaves the local representing the `resume` argument in place,
     // but turns it into a regular local variable. This is cheaper than
     // adjusting all local references in the body after removing it.
@@ -1733,7 +1733,7 @@ impl<'tcx> MirPass<'tcx> for StateTransform {
 
         // Remove the context argument within generator bodies.
         if matches!(coroutine_kind, CoroutineKind::Desugared(CoroutineDesugaring::Gen, _)) {
-            transform_gen_context(tcx, body);
+            transform_gen_context(body);
         }
 
         // The original arguments to the function are no longer arguments, mark them as such.
diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
index be19bd8349e..956d855ab81 100644
--- a/compiler/rustc_mir_transform/src/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -2,6 +2,7 @@
 use crate::deref_separator::deref_finder;
 use rustc_attr::InlineAttr;
 use rustc_const_eval::transform::validate::validate_types;
+use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
 use rustc_index::bit_set::BitSet;
 use rustc_index::Idx;
@@ -384,6 +385,17 @@ impl<'tcx> Inliner<'tcx> {
                 }
 
                 let fn_sig = self.tcx.fn_sig(def_id).instantiate(self.tcx, args);
+
+                // Additionally, check that the body that we're inlining actually agrees
+                // with the ABI of the trait that the item comes from.
+                if let InstanceDef::Item(instance_def_id) = callee.def
+                    && self.tcx.def_kind(instance_def_id) == DefKind::AssocFn
+                    && let instance_fn_sig = self.tcx.fn_sig(instance_def_id).skip_binder()
+                    && instance_fn_sig.abi() != fn_sig.abi()
+                {
+                    return None;
+                }
+
                 let source_info = SourceInfo { span: fn_span, ..terminator.source_info };
 
                 return Some(CallSite { callee, fn_sig, block: bb, source_info });
diff --git a/compiler/rustc_mir_transform/src/instsimplify.rs b/compiler/rustc_mir_transform/src/instsimplify.rs
index f65eb5cbea9..06df89c1037 100644
--- a/compiler/rustc_mir_transform/src/instsimplify.rs
+++ b/compiler/rustc_mir_transform/src/instsimplify.rs
@@ -29,17 +29,14 @@ impl<'tcx> MirPass<'tcx> for InstSimplify {
                         ctx.simplify_bool_cmp(&statement.source_info, rvalue);
                         ctx.simplify_ref_deref(&statement.source_info, rvalue);
                         ctx.simplify_len(&statement.source_info, rvalue);
-                        ctx.simplify_cast(&statement.source_info, rvalue);
+                        ctx.simplify_cast(rvalue);
                     }
                     _ => {}
                 }
             }
 
             ctx.simplify_primitive_clone(block.terminator.as_mut().unwrap(), &mut block.statements);
-            ctx.simplify_intrinsic_assert(
-                block.terminator.as_mut().unwrap(),
-                &mut block.statements,
-            );
+            ctx.simplify_intrinsic_assert(block.terminator.as_mut().unwrap());
             ctx.simplify_nounwind_call(block.terminator.as_mut().unwrap());
             simplify_duplicate_switch_targets(block.terminator.as_mut().unwrap());
         }
@@ -143,7 +140,7 @@ impl<'tcx> InstSimplifyContext<'tcx, '_> {
         }
     }
 
-    fn simplify_cast(&self, _source_info: &SourceInfo, rvalue: &mut Rvalue<'tcx>) {
+    fn simplify_cast(&self, rvalue: &mut Rvalue<'tcx>) {
         if let Rvalue::Cast(kind, operand, cast_ty) = rvalue {
             let operand_ty = operand.ty(self.local_decls, self.tcx);
             if operand_ty == *cast_ty {
@@ -277,11 +274,7 @@ impl<'tcx> InstSimplifyContext<'tcx, '_> {
         }
     }
 
-    fn simplify_intrinsic_assert(
-        &self,
-        terminator: &mut Terminator<'tcx>,
-        _statements: &mut Vec<Statement<'tcx>>,
-    ) {
+    fn simplify_intrinsic_assert(&self, terminator: &mut Terminator<'tcx>) {
         let TerminatorKind::Call { func, target, .. } = &mut terminator.kind else {
             return;
         };