fix missing Const

src/ParallelKernel/EnzymeExt/autodiff_gpu.jl

@@ -8,12 +8,25 @@ import Enzyme
 #     end
 # end
 
+function promoto_to_const(args...)
+    ntuple(length(args)) do i
+        @inbounds
+        if !(args[i] isa Enzyme.Annotation)
+            return Enzyme.Const(args[i])
+        else
+            return args[i]
+        end
+    end
+end
+
 function ParallelStencil.ParallelKernel.AD.autodiff_deferred!(arg, args...) # NOTE: minimal specialization is used to avoid overwriting the default method
+    args = promote_to_const(args...)
     Enzyme.autodiff_deferred(arg, args...)
     return
 end
 
 function ParallelStencil.ParallelKernel.AD.autodiff_deferred_thunk!(arg, args...) # NOTE: minimal specialization is used to avoid overwriting the default method
+    args = promote_to_const(args...)
     Enzyme.autodiff_deferred_thunk(arg, args...)
     return
 end

test/ParallelKernel/test_parallel.jl

@@ -114,10 +114,10 @@ import Enzyme
                         return
                     end
                     # Enzyme requires explicit argument annotation, PS injects arguments without annotation
-                    # @parallel configcall=f!(A, B, a) AD.autodiff_deferred!(Enzyme.Reverse, Const(f!), DuplicatedNoNeed(A, Ā), DuplicatedNoNeed(B, B̄), Const(a))
+                    @parallel configcall=f!(A, B, a) AD.autodiff_deferred!(Enzyme.Reverse, Const(f!), DuplicatedNoNeed(A, Ā), DuplicatedNoNeed(B, B̄), Const(a))
                     Enzyme.autodiff_deferred(Enzyme.Reverse, Const(g!), DuplicatedNoNeed(A_ref, Ā_ref), DuplicatedNoNeed(B_ref, B̄_ref), Const(a))
-                    # @test Array(Ā) ≈ Ā_ref
-                    # @test Array(B̄) ≈ B̄_ref
+                    @test Array(Ā) ≈ Ā_ref
+                    @test Array(B̄) ≈ B̄_ref
                 end
             end
             @testset "@parallel_indices" begin