diff --git a/src/compiler.jl b/src/compiler.jl
index b3a01cd9c0..2554dbbab6 100644
--- a/src/compiler.jl
+++ b/src/compiler.jl
@@ -7160,6 +7160,9 @@ function ptr_rule(direction::Cint, ret::API.CTypeTreeRef, args::Ptr{API.CTypeTre
 end
 
 function inout_rule(direction::Cint, ret::API.CTypeTreeRef, args::Ptr{API.CTypeTreeRef}, known_values::Ptr{API.IntList}, numArgs::Csize_t, val::LLVM.API.LLVMValueRef)::UInt8
+    if numArgs != 1
+        return UInt8(false)
+    end
     inst = LLVM.Instruction(val)
     ce = operands(inst)[1]
     while isa(ce, ConstantExpr)
diff --git a/test/runtests.jl b/test/runtests.jl
index 702240454d..beed52c511 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -297,6 +297,9 @@ end
     end
     @test autodiff(Reverse, f9, Active, Active(2.0))[1][1] == 8
     @test autodiff(Forward, f9, Duplicated(2.0, 1.0))[1]   == 8
+
+    f10(x) = hypot(x, 2x)
+    @test autodiff(Reverse, f10, Active, Active(2.0))[1][1] == sqrt(5)
 end
 
 @testset "Taylor series tests" begin