diff --git a/lib/unparser/emitter/op_assign.rb b/lib/unparser/emitter/op_assign.rb
index 52d3d117..affd028a 100644
--- a/lib/unparser/emitter/op_assign.rb
+++ b/lib/unparser/emitter/op_assign.rb
@@ -35,6 +35,11 @@ class OpAssign < self
 
       children :target, :operator, :value
 
+      def emit_heredoc_reminders
+        emitter(target).emit_heredoc_reminders
+        emitter(value).emit_heredoc_reminders
+      end
+
     private
 
       def dispatch
diff --git a/test/corpus/semantic/opasgn.rb b/test/corpus/semantic/opasgn.rb
new file mode 100644
index 00000000..de66f430
--- /dev/null
+++ b/test/corpus/semantic/opasgn.rb
@@ -0,0 +1 @@
+y += "#{42}\n"