Missing 2-argument method for bitcast!

[MilesCranmer]

I think this line:

Enzyme.jl/src/compiler.jl

Line 6622 in 5fc2309

tape = bitcast!(builder, LLVM.PointerType(llty, LLVM.addrspace(value_type(tape))))

calls a method that does not exist? We are running into an error for it here: SymbolicML/DynamicExpressions.jl#91 (comment)

Test enzyme derivatives: Error During Test at /home/runner/.julia/packages/SafeTestsets/raUNr/src/SafeTestsets.jl:30
  Got exception outside of a @test
  LoadError: MethodError: no method matching bitcast!(::LLVM.IRBuilder, ::LLVM.PointerType)
  
  Closest candidates are:
    bitcast!(::LLVM.IRBuilder, ::LLVM.Value, ::LLVM.LLVMType, ::String)
     @ LLVM ~/.julia/packages/LLVM/5DlHM/src/irbuilder.jl:343
    bitcast!(::LLVM.IRBuilder, ::LLVM.Value, ::LLVM.LLVMType)
     @ LLVM ~/.julia/packages/LLVM/5DlHM/src/irbuilder.jl:343
  
  Stacktrace:
    [1] #28366
      @ ~/.julia/packages/Enzyme/aEyGD/src/compiler.jl:6622 [inlined]
    [2] JuliaContext(f::Enzyme.Compiler.var"#28366#28371"{Bool, DataType, DataType, DataType, Int64, DataType, Int64, Bool, DataType, DataType}; kwargs::@Kwargs{})
      @ GPUCompiler ~/.julia/packages/GPUCompiler/Y4hSX/src/driver.jl:52
    [3] JuliaContext(f::Function)
      @ GPUCompiler ~/.julia/packages/GPUCompiler/Y4hSX/src/driver.jl:42
    [4] #s2028#28365
      @ ~/.julia/packages/Enzyme/aEyGD/src/compiler.jl:6276 [inlined]
    [5] var"#s2028#28365"(RawCall::Any, PT::Any, FA::Any, T::Any, RT::Any, TapeType::Any, N::Any, CC::Any, width::Any, returnPrimal::Any, ::Any, ::Type, fptr::Any, ::Type, ::Type, ::Type, tt::Any, rt::Any, fn::Any, ::Any, args::Any)
      @ Enzyme.Compiler ./none:0
    [6] (::Core.GeneratedFunctionStub)(::UInt64, ::LineNumberNode, ::Any, ::Vararg{Any})
      @ Core ./boot.jl:602

[wsmoses]

@MilesCranmer can you see if this fixes it: #1679

[MilesCranmer]

It looks like there just isn't a 2-argument bitcast! method in LLVM.jl though, unless I am mistaken?

julia> using LLVM

julia> LLVM.bitcast! |> methods
# 2 methods for generic function "bitcast!" from LLVM:
 [1] bitcast!(builder::IRBuilder, Val::Value, DestTy::LLVMType, Name::String)
     @ ~/.julia/packages/LLVM/5DlHM/src/irbuilder.jl:343
 [2] bitcast!(builder::IRBuilder, Val::Value, DestTy::LLVMType)
     @ ~/.julia/packages/LLVM/5DlHM/src/irbuilder.jl:343

[wsmoses]

whoops sorry put arg in the wrong place, retry?

[MilesCranmer]

Thanks, that fixed the original issue. Now I get a segfault, though presumably it's from something different? https://github.com/SymbolicML/DynamicExpressions.jl/actions/runs/10117201276/job/27981679660?pr=91#step:6:523. Will

[wsmoses]

Seemingly different -- but having an absolute MWE of that would be immensely useful to fix