diff --git a/src/ir/child-typer.h b/src/ir/child-typer.h
index 089b21f86e0..5a374f89b8e 100644
--- a/src/ir/child-typer.h
+++ b/src/ir/child-typer.h
@@ -1249,8 +1249,11 @@ template<typename Subtype> struct ChildTyper : OverriddenVisitor<Subtype> {
     Type type = ht->getArray().element.type;
     note(&curr->ref, Type(*ht, Nullable));
     note(&curr->index, Type::i32);
-    // TODO: (shared eq) as appropriate.
-    note(&curr->expected, type.isRef() ? Type(HeapType::eq, Nullable) : type);
+    note(
+      &curr->expected,
+      type.isRef()
+        ? Type(HeapTypes::eq.getBasic(type.getHeapType().getShared()), Nullable)
+        : type);
     note(&curr->replacement, type);
   }
 
diff --git a/test/lit/basic/gc-atomics-shared.wast b/test/lit/basic/gc-atomics-shared.wast
new file mode 100644
index 00000000000..818239c1569
--- /dev/null
+++ b/test/lit/basic/gc-atomics-shared.wast
@@ -0,0 +1,55 @@
+;; NOTE: Assertions have been generated by update_lit_checks.py and should not be edited.
+
+;; RUN: wasm-opt -all %s -S -o - | filecheck %s
+
+;; Check that we properly parse array.atomic.rmw.cmpxchg of a shared array,
+;; when the instruction is unreachable (when the the expected field does not
+;; have the correct sharedness).
+
+(module
+  ;; CHECK:      (type $array (shared (array (mut (ref null (shared eq))))))
+  (type $array (shared (array (mut (ref null (shared eq))))))
+
+  ;; CHECK:      (global $g (ref $array) (array.new_default $array
+  ;; CHECK-NEXT:  (i32.const 0)
+  ;; CHECK-NEXT: ))
+  (global $g (ref $array) (array.new_default $array (i32.const 0)))
+
+  ;; CHECK:      (func $test (type $1) (result (ref null (shared eq)))
+  ;; CHECK-NEXT:  (drop
+  ;; CHECK-NEXT:   (global.get $g)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (drop
+  ;; CHECK-NEXT:   (i32.const 0)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (drop
+  ;; CHECK-NEXT:   (ref.as_non_null
+  ;; CHECK-NEXT:    (ref.null none)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT:  (block ;; (replaces unreachable ArrayCmpxchg we can't emit)
+  ;; CHECK-NEXT:   (drop
+  ;; CHECK-NEXT:    (unreachable)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (drop
+  ;; CHECK-NEXT:    (unreachable)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (drop
+  ;; CHECK-NEXT:    (unreachable)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (drop
+  ;; CHECK-NEXT:    (unreachable)
+  ;; CHECK-NEXT:   )
+  ;; CHECK-NEXT:   (unreachable)
+  ;; CHECK-NEXT:  )
+  ;; CHECK-NEXT: )
+  (func $test (result (ref null (shared eq)))
+    (array.atomic.rmw.cmpxchg acqrel acqrel $array
+      (global.get $g)
+      (i32.const 0)
+      (ref.as_non_null (ref.null none))
+      (unreachable)
+    )
+  )
+)
+