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Author: mcabbott

src/layers/normalise.jl

@@ -275,6 +275,7 @@ function _track_stats!(
   μnew = vec(N ∈ reduce_dims ? μ : mean(μ, dims=N))
   σ²new = vec(N ∈ reduce_dims ? σ² : mean(σ², dims=N))
 
+  # ForwardDiff.value removes Dual, was an error, issue #2122
   bn.μ .= value.(res_mtm .* bn.μ .+ mtm .* μnew)
   bn.σ² .= value.(res_mtm .* bn.σ² .+ mtm .* (m / (m - one(V))) .* σ²new)
   return nothing

test/layers/normalisation.jl

@@ -472,6 +472,7 @@ end
   @test ForwardDiff.jacobian(bn, rand(Float32, 3, 4)) isa Matrix{Float32}
   iszero(bn.μ)  # true, but ideally it would automatically choose trainmode
   Flux.trainmode!(bn)
+  # This was an error, https://github.com/FluxML/Flux.jl/issues/2122
   @test ForwardDiff.jacobian(bn, rand(Float32, 3, 4)) isa Matrix{Float32}
   @test !iszero(bn.μ)
 end