fixes #164

src/tracker/array.jl

@@ -130,8 +130,8 @@ LinAlg.dot(xs::AbstractVector, ys::TrackedVector) = track(dot, xs, ys)
 LinAlg.dot(xs::TrackedVector, ys::AbstractVector) = track(dot, xs, ys)
 
 function back(::typeof(dot), Δ, xs, ys)
-  @back(xs, Δ.*ys)
-  @back(ys, Δ.*xs)
+  @back(xs, Δ.*data(ys))
+  @back(ys, Δ.*data(xs))
 end
 
 # Hacks to get std working

test/tracker.jl

@@ -45,6 +45,7 @@ end
 @test gradtest(x -> std(x, 1), rand(5,5))
 
 @test gradtest((x, y) -> x .* y, rand(5), rand(5))
+@test gradtest(dot, rand(5), rand(5))
 
 @test gradtest(rand(5)) do x
   y = x.^2