module Foo

using Serialization

struct Bar
    x::Int
end

function __init__()
    mktemp() do path, io
        serialize(io, Bar(42))
    end
end

end # module Foo

ERROR: InitError: KeyError: key Foo not found
Stacktrace:
  [1] getindex
    @ ./iddict.jl:98 [inlined]
  [2] macro expansion
    @ ./lock.jl:273 [inlined]
  [3] root_module_key
    @ ./loading.jl:2420
  [4] serialize_mod_names
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:390
  [5] serialize
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:402 [inlined]
  [6] serialize_type_data
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:595
  [7] serialize_type
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:627
  [8] serialize_any
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:0
  [9] serialize
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:680 [inlined]
 [10] serialize
    @ ~/.julia/juliaup/julia-1.11.2+0.aarch64.apple.darwin14/share/julia/stdlib/v1.11/Serialization/src/Serialization.jl:807 [inlined]
 [11] #1
    @ ~/Projects/Foo/src/Foo.jl:11 [inlined]
 [12] mktemp
    @ ./file.jl:790
 [13] mktemp
    @ ./file.jl:788 [inlined]
 [14] __init__()
    @ Foo ~/Projects/Foo/src/Foo.jl:10
 [15] run_module_init(mod::Module, i::Int64)
    @ Base ./loading.jl:1378
 [16] register_restored_modules(sv::Core.SimpleVector, pkg::Base.PkgId, path::String)
    @ Base ./loading.jl:1366
 [17] _include_from_serialized(pkg::Base.PkgId, path::String, ocachepath::String, depmods::Vector{Any}, ignore_native::Nothing; register::Bool)
    @ Base ./loading.jl:1254
 [18] _include_from_serialized (repeats 2 times)
    @ ./loading.jl:1210 [inlined]
 [19] _require_search_from_serialized(pkg::Base.PkgId, sourcepath::String, build_id::UInt128, stalecheck::Bool; reasons::Dict{String, Int64}, DEPOT_PATH::Vector{String})
    @ Base ./loading.jl:2057
 [20] _require(pkg::Base.PkgId, env::String)
    @ Base ./loading.jl:2527
 [21] __require_prelocked(uuidkey::Base.PkgId, env::String)
    @ Base ./loading.jl:2388
 [22] #invoke_in_world#3
    @ ./essentials.jl:1089 [inlined]
 [23] invoke_in_world
    @ ./essentials.jl:1086 [inlined]
 [24] _require_prelocked(uuidkey::Base.PkgId, env::String)
    @ Base ./loading.jl:2375
 [25] macro expansion
    @ ./loading.jl:2314 [inlined]
 [26] macro expansion
    @ ./lock.jl:273 [inlined]
 [27] __require(into::Module, mod::Symbol)
    @ Base ./loading.jl:2271
 [28] #invoke_in_world#3
    @ ./essentials.jl:1089 [inlined]
 [29] invoke_in_world
    @ ./essentials.jl:1086 [inlined]
 [30] require(into::Module, mod::Symbol)
    @ Base ./loading.jl:2260
during initialization of module Foo