diff --git a/src/samplefunctional.hh b/src/samplefunctional.hh
index 7a2f63bac59770c3e948ff7ec8a0397358403ec3..afecb5c3d326542d7088940c2c4965c6eb9a93f9 100644
--- a/src/samplefunctional.hh
+++ b/src/samplefunctional.hh
@@ -147,6 +147,8 @@ void minimise(const Functional J, const typename Functional::SmallVector x,
   MyNonlinearityType phi = J.phi;
   typedef DirectionalConvexFunction<MyNonlinearityType>
   MyDirectionalConvexFunctionType;
+  // FIXME: We cannot pass J.phi directly because the constructor
+  // does not allow for constant arguments
   MyDirectionalConvexFunctionType JRest(JRestA, JRestb, phi, x, descDir);
   // }}}