diff --git a/src/compiler/interface.jl b/src/compiler/interface.jl
index 70b86775b..fb4e0a3e8 100644
--- a/src/compiler/interface.jl
+++ b/src/compiler/interface.jl
@@ -41,7 +41,7 @@ tailmemaybe(::Nothing) = nothing
 tailmemaybe(x::Tuple) = Base.tail(x)
 
 replacezero(x) = x
-replacezero(::Nothing) = @warn "Use of 'nothing' to represent zero gradients is deprecated, use Zero() or DoesNotExist() from ChainRules"; return nothing
+replacezero(::Nothing) = Base.depwarn("Use of 'nothing' to represent zero gradients is deprecated, use Zero() or DoesNotExist() from ChainRules", :replacezero); return nothing
 replacezero(::AbstractZero) = nothing
 replacezero(t::Tuple) = ntuple(i -> replacezero(t[i]), length(t))
 
diff --git a/src/lib/lib.jl b/src/lib/lib.jl
index 6f06a458e..73b84e43e 100644
--- a/src/lib/lib.jl
+++ b/src/lib/lib.jl
@@ -166,7 +166,7 @@ unapply(t, xs) = _unapply(t, xs)[1]
     if Δ isa AbstractZero
       return Δ
     elseif Δ === nothing
-        println("hit 'nothing' in Core._apply")
+      println("hit 'nothing' in Core._apply")
       return Zero()
     else
       (first(Δ), unapply(st, Base.tail(Δ))...)