hotfix scalar path

Author: ChrisRackauckas

Project.toml

@@ -1,7 +1,7 @@
 name = "RecursiveArrayTools"
 uuid = "731186ca-8d62-57ce-b412-fbd966d074cd"
 authors = ["Chris Rackauckas <[email protected]>"]
-version = "3.18.0"
+version = "3.18.1"
 
 [deps]
 Adapt = "79e6a3ab-5dfb-504d-930d-738a2a938a0e"

ext/RecursiveArrayToolsReverseDiffExt.jl

@@ -9,8 +9,8 @@ function trackedarraycopyto!(dest, src)
     for (i, slice) in zip(eachindex(dest.u), eachslice(src, dims = ndims(src)))
         if dest.u[i] isa AbstractArray
             dest.u[i] = reshape(ArrayInterface.aos_to_soa(slice), size(dest.u[i]))
-        elseif dest.u[i]
-            trackedarraycopyto!(dest.u[i], slice)
+        elseif dest.u[i] isa Number
+            dest.u[i] = slice
         end
     end
 end