diff --git a/REQUIRE b/REQUIRE
index 1800eb5a..a413dea2 100644
--- a/REQUIRE
+++ b/REQUIRE
@@ -1,4 +1,4 @@
-julia 0.5
+julia 0.6-
 Juno 0.2.6
 Lazy 0.11.3
 LNR
diff --git a/src/profiler/tree.jl b/src/profiler/tree.jl
index 45a32190..d737aa27 100644
--- a/src/profiler/tree.jl
+++ b/src/profiler/tree.jl
@@ -1,7 +1,8 @@
 type Tree{T}
   head::T
   children::Vector{Tree{T}}
-  Tree(x::T, children = Tree{T}[]) = new(x, children)
+  Tree{T}(x::T, children = Tree{T}[]) where T =
+    new{T}(x, children)
 end
 
 Tree(x, children = []) = Tree{typeof(x)}(x, children)