`ERROR: BoundsError: attempt to access 0-element Vector{Any} at index [2]` in `indexed_iterate`

julia> using LinearAlgebra, Cthulhu

julia> @descend (A -> ((λ,v) = eigen(A); (λ,v)))(rand(2,2))
(::var"#3#4")(A) @ Main REPL[8]:1
┌ Warning: couldn't retrieve source of (::var"#3#4")(A) @ Main REPL[8]:1
└ @ TypedSyntax ~/.julia/packages/TypedSyntax/AZkb2/src/node.jl:31
Variables
  #self#::Core.Const(var"#3#4"())
  A::Matrix{Float64}
  @_3::Val{:vectors}
  v::Union{Matrix{ComplexF64}, Matrix{Float64}}
  λ::Union{Vector{ComplexF64}, Vector{Float64}}

∘ ─ %0 = invoke #3(::Matrix{Float64})::Tuple{Union{Vector{ComplexF64}, Vector{Float64}}, Union{Matrix{ComplexF64}, Matrix{Float64}}}
    @ REPL[8]:1 within `#3`
1 ─ %1 = Main.eigen(A)::Union{Eigen{ComplexF64, ComplexF64, Matrix{ComplexF64}, Vector{ComplexF64}}, Eigen{Float64, Float64, Matrix{Float64}, Vector{Float64}}}
│   %2 = Base.indexed_iterate(%1, 1)::Union{Tuple{Vector{ComplexF64}, Val{:vectors}}, Tuple{Vector{Float64}, Val{:vectors}}}
│        (λ = Core.getfield(%2, 1))::Union{Vector{ComplexF64}, Vector{Float64}}
│        (@_3 = Core.getfield(%2, 2))::Core.Const(Val{:vectors}())
│   %5 = Base.indexed_iterate(%1, 2, @_3)::Union{Tuple{Matrix{ComplexF64}, Val{:done}}, Tuple{Matrix{Float64}, Val{:done}}}
│        (v = Core.getfield(%5, 1))::Union{Matrix{ComplexF64}, Matrix{Float64}}
│   %7 = Core.tuple(λ, v)::Tuple{Union{Vector{ComplexF64}, Vector{Float64}}, Union{Matrix{ComplexF64}, Matrix{Float64}}}
└──      return %7
Select a call to descend into or ↩ to ascend. [q]uit. [b]ookmark.
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   %1 = eigen(::Matrix{Float64})::Union{Eigen{ComplexF64, ComplexF64, Matrix{ComplexF64}, Vector{ComplexF64}}, Eigen{Float64, Float64, Matrix{Float64}, Vector{Float64}}}
 • %2 = call → indexed_iterate(::Union{Eigen{ComplexF64, ComplexF64, Matrix{ComplexF64}, Vector{ComplexF64}}, Eigen{Float64, Float64, Matrix{Float64}, Vector{Float64}}},::Int64)::…
   %5 = call → indexed_iterate(…,…,…)::Union{Tuple{Matrix{ComplexF64}, Val{:done}}, Tuple{Matrix{Float64}, Val{:done}}}
   ↩

 • %2 =  = < semi-concrete eval > indexed_iterate(::Eigen{ComplexF64, ComplexF64, Matrix{ComplexF64}, Vector{ComplexF64}},::Core.Const(1))::…
   %2 =  = < semi-concrete eval > indexed_iterate(::Eigen{Float64, Float64, Matrix{Float64}, Vector{Float64}},::Core.Const(1))::…
   ↩
[ Info: tracking Base
ERROR: BoundsError: attempt to access 0-element Vector{Any} at index [2]
Stacktrace:
  [1] getindex
    @ ./essentials.jl:13 [inlined]
  [2] getindex
    @ ./compiler/ssair/ir.jl:243 [inlined]
  [3] getindex
    @ ./compiler/ssair/ir.jl:1059 [inlined]
  [4] getindex
    @ ./compiler/ssair/ir.jl:1044 [inlined]
  [5] abstract_eval_ssavalue
    @ ./compiler/optimize.jl:373 [inlined]
  [6] argextype(x::Any, src::Core.Compiler.IRCode, sptypes::Vector{Any}, slottypes::Vector{Any})
    @ Core.Compiler ./compiler/optimize.jl:358
  [7] #15
    @ ~/Dropbox/JuliaPackages/Cthulhu.jl/src/reflection.jl:45 [inlined]
  [8] map!(f::Cthulhu.var"#15#16"{Core.Compiler.IRCode, Vector{Any}, Vector{Any}}, dest::Vector{Any}, A::Vector{Any})
    @ Base ./abstractarray.jl:3254
  [9] mapany(f::Function, A::Vector{Any})
    @ Base ./abstractarray.jl:3263
 [10] find_callsites(interp::Cthulhu.CthulhuInterpreter, CI::Core.Compiler.IRCode, stmt_infos::Vector{Core.Compiler.CallInfo}, mi::Core.MethodInstance, slottypes::Vector{Any}, optimize::Bool, annotate_source::Bool)
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/reflection.jl:44
 [11] _descend(term::REPL.Terminals.TTYTerminal, interp::Cthulhu.CthulhuInterpreter, curs::Cthulhu.CthulhuCursor; override::Cthulhu.SemiConcreteCallInfo, debuginfo::Cthulhu.DInfo.DebugInfo, optimize::Bool, interruptexc::Bool, iswarn::Bool, hide_type_stable::Bool, verbose::Nothing, remarks::Bool, with_effects::Bool, inline_cost::Bool, type_annotations::Bool, annotate_source::Bool)
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:501
 [12] _descend(term::REPL.Terminals.TTYTerminal, interp::Cthulhu.CthulhuInterpreter, curs::Cthulhu.CthulhuCursor; override::Nothing, debuginfo::Symbol, optimize::Bool, interruptexc::Bool, iswarn::Bool, hide_type_stable::Bool, verbose::Nothing, remarks::Bool, with_effects::Bool, inline_cost::Bool, type_annotations::Bool, annotate_source::Bool)
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:634
 [13] _descend
    @ ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:418 [inlined]
 [14] #_descend#107
    @ ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:770 [inlined]
 [15] _descend
    @ ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:770 [inlined]
 [16] #_descend#110
    @ ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:786 [inlined]
 [17] __descend_with_error_handling(args::Any; terminal::Any, kwargs::Base.Pairs{Symbol, V, Tuple{Vararg{Symbol, N}}, NamedTuple{names, T}} where {V, N, names, T<:Tuple{Vararg{Any, N}}})
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:244
 [18] _descend_with_error_handling(f::Any, argtypes::Any; kwargs::Base.Pairs{Symbol, Bool, Tuple{Symbol}, NamedTuple{(:iswarn,), Tuple{Bool}}})
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:233
 [19] descend_code_typed(::Any, ::Vararg{Any}; kwargs::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:178
 [20] descend_code_typed(::Any, ::Any)
    @ Cthulhu ~/Dropbox/JuliaPackages/Cthulhu.jl/src/Cthulhu.jl:178
 [21] top-level scope
    @ REPL[8]:1

This is continuing https://github.com/JuliaDebug/Cthulhu.jl/issues/443 after the fix in https://github.com/JuliaDebug/Cthulhu.jl/pull/444.

Reproduce the failure with the Julia REPL example in the issue, then inspect find_callsites in src/reflection.jl around line 44 and the _descend path in src/Cthulhu.jl. Compare this continuation with issue 443 and pull request 444, and consider the issue resolved when the same descent no longer raises the BoundsError.