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Co-authored-by: David Widmann <devmotion@users.noreply.github.com>
Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>

src/rule_definition_tools.jl

@@ -297,9 +297,9 @@ function propagation_expr(Δs, ∂s, _conj=false, proj=identity)
     (∂s_1, Δs_1), _∂s_Δs_tail = Iterators.peel(zip(_∂s, Δs))
     # zero gradients are treated as hard zeros. This avoids propagation of NaNs when
     # partials are non-finite
-    init_expr = :(ifelse(iszero($Δs_1), zero($∂s_1), $∂s_1) * $Δs_1)
+    init_expr = :((iszero($Δs_1) ? zero($∂s_1) : $∂s_1) * $Δs_1)
     summed_∂_mul_Δs = foldl(_∂s_Δs_tail; init=init_expr) do ex, (∂s_i, Δs_i)
-        :(muladd(ifelse(iszero($Δs_i), zero($∂s_i), $∂s_i), $Δs_i, $ex))
+        :(muladd((iszero($Δs_i) ? zero($∂s_i) : $∂s_i), $Δs_i, $ex))
     end
     return :($proj($summed_∂_mul_Δs))
 end

test/rule_definition_tools.jl

@@ -262,7 +262,7 @@ end
 
             @test frule((NoTangent(), 1.0, 1.0), suminv, 0.0, 1.0) === (Inf, -Inf)
             @test frule((NoTangent(), ZeroTangent(), 1.0), suminv, 0.0, 1.0) === (Inf, -1.0)
-            @test frule((NoTangent(), 0.0, 1.0), suminv, 0.0, 1.0) === (Inf, -1.0)            
+            @test frule((NoTangent(), 0.0, 1.0), suminv, 0.0, 1.0) === (Inf, -1.0)
 
             @test frule((NoTangent(), 1.0, 1.0), suminv, 1.0, 0.0) === (Inf, -Inf)
             @test frule((NoTangent(), 1.0, ZeroTangent()), suminv, 1.0, 0.0) === (Inf, -1.0)