EnzymeInternalError differentiating DynamicExpressions ParametricExpression eval_tree_array

This came up while testing `SymbolicRegression.jl` `ParametricExpression` support with Enzyme. I was able to reduce it to a direct `DynamicExpressions.jl` + `Enzyme.jl` reproducer below. Full verbose log and the standalone script are in this gist: https://gist.github.com/MilesCranmerBot/ab94e22b108efbcd83eb0f6e63c453d2 ## Reproducer ```julia using DynamicExpressions using Enzyme using Random: MersenneTwister Enzyme.Compiler.VERBOSE_ERRORS[] = true rng = MersenneTwister(0) X = rand(rng, 2, 32) class = rand(rng, 1:2, 32) operators = OperatorEnum(; unary_operators=[cos], binary_operators=[+, *, -]) ex = @parse_expression( x * x - cos(2.5 * y + -0.5) + p1, operators=operators, expression_type=ParametricExpression, variable_names=["x", "y"], extra_metadata=(parameter_names=["p1"], parameters=[0.1 0.2]), ) function f(ex, X, class, operators, output) pred, ok = eval_tree_array(ex, X, class, operators) output[] = ok ? sum(abs2, pred) : Inf return nothing end dex = Enzyme.make_zero(ex) dX = zero(X) output = [0.0] doutput = [1.0] Enzyme.autodiff( Reverse, f, Duplicated(ex, dex), Duplicated(X, dX), Const(class), Const(operators), Duplicated(output, doutput), ) ``` ## Error This fails with: ```text ERROR: LoadError: EnzymeInternalError: Enzyme compilation failed due to an internal error. Please open an issue with the code to reproduce and full error log on github.com/EnzymeAD/Enzyme.jl To toggle more information for debugging (needed for bug reports), set Enzyme.Compiler.VERBOSE_ERRORS[] = true (default false) ... Illegal address space propagation + rep: %2 = alloca ptr addrspace(10), i64 1, align 8, !enzymejl_allocart !74, !enzyme_type !75, !enzymejl_allocart_name !77 + prev: %3 = addrspacecast ptr %2 to ptr addrspace(10), !enzyme_backstack !0 + inst: %root_phi.in = phi ptr addrspace(10) [ %9, %L90 ], [ %7, %L88 ], [ %3, %L82 ], !dbg !182 Stacktrace: [1] macro expansion @ ~/.julia/packages/DynamicExpressions/ERjoe/src/Evaluate.jl:550 [2] dispatch_deg1_l2_ll0_lr0_eval @ ~/.julia/packages/DynamicExpressions/ERjoe/src/Evaluate.jl:534 [3] macro expansion @ ~/.julia/packages/DynamicExpressions/ERjoe/src/Evaluate.jl:512 [4] dispatch_deg1_eval @ ~/.julia/packages/DynamicExpressions/ERjoe/src/Evaluate.jl:481 ``` ## Environment ```text Julia Version 1.12.5 OS: Linux (x86_64-linux-gnu) CPU: 12 x AMD EPYC-Genoa Processor LLVM: libLLVM-18.1.7 (ORCJIT, znver4) Threads: 12 default, 1 interactive, 12 GC Enzyme 0.13.150 DynamicExpressions 2.5.2 ``` I originally hit the same internal error via `SymbolicRegression.jl` `v2.0.0-alpha.11` / commit `482530b64cfd9b96cb1b6162de0ad5b763e8e6b0`, with the stack passing through `SymbolicRegression/src/ParametricExpression.jl:93` into `DynamicExpressions.Evaluate.jl:550`.