diff --git a/src/compiler/loops.jl b/src/compiler/loops.jl
index 47704a5a..14a708fd 100644
--- a/src/compiler/loops.jl
+++ b/src/compiler/loops.jl
@@ -3,7 +3,7 @@ export unroll, unroll1
 struct Offset
   name::Symbol
   n::Int
-  default::Nullable{Param}
+  default::Nullable{Any}
 end
 
 Offset(name, n) = Offset(name, n, nothing)