Remove unneeded return from void functions
diff --git a/gen/write.rs b/gen/write.rs
index b745739..3d1fdf3 100644
--- a/gen/write.rs
+++ b/gen/write.rs
@@ -821,12 +821,12 @@
 
     writeln!(out, "template <>");
     writeln!(out, "void Box<{}>::uninit() noexcept {{", inner);
-    writeln!(out, "  return cxxbridge02$box${}$uninit(this);", instance);
+    writeln!(out, "  cxxbridge02$box${}$uninit(this);", instance);
     writeln!(out, "}}");
 
     writeln!(out, "template <>");
     writeln!(out, "void Box<{}>::drop() noexcept {{", inner);
-    writeln!(out, "  return cxxbridge02$box${}$drop(this);", instance);
+    writeln!(out, "  cxxbridge02$box${}$drop(this);", instance);
     writeln!(out, "}}");
 }