diff --git a/src/KahanSummation.jl b/src/KahanSummation.jl
index 8bb79db..fde6700 100644
--- a/src/KahanSummation.jl
+++ b/src/KahanSummation.jl
@@ -23,6 +23,12 @@ else
     end
 end
 
+if isdefined(Base, :promote_sys_size_add)
+    using Base: promote_sys_size_add
+else
+    promote_sys_size_add(x::T) where {T} = Base.r_promote(+, zero(T)::T)
+end
+
 """
     cumsum_kbn(A, dim::Integer)
 
@@ -87,7 +93,7 @@ summation algorithm for additional accuracy.
 """
 function sum_kbn(A)
     T = @default_eltype(typeof(A))
-    c = Base.promote_sys_size_add(zero(T)::T)
+    c = promote_sys_size_add(zero(T)::T)
     i = start(A)
     if done(A, i)
         return c
diff --git a/test/runtests.jl b/test/runtests.jl
index 4301490..133e2e5 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -5,6 +5,9 @@ using KahanSummation
 using Compat
 using Compat.Test
 
+# Shadow the names in Base if they're defined
+import KahanSummation: sum_kbn, cumsum_kbn
+
 @testset "cumsum_kbn" begin
     v   = [1,1e100,1,-1e100]*1000
     v2  = [1,-1e100,1,1e100]*1000