"AssertionError: Found non concrete return type"

[DilumAluthge]

Originally posted as issue FluxML/Flux.jl#325, but reposted here because it seems to be more of a CLArrays/Transpiler error than a Flux error.

This issue seems to be similar to issue #5 in this repo.

---

Here's the code snippet that I am trying to run (based on the Flux linear regression example here):

import CLArrays
W = rand(CLArrays.CLArray{Float32}, 2, 5)
b = rand(CLArrays.CLArray{Float32}, 2)
predict(x) = W*x .+ b
loss(x, y) = sum((predict(x) .- y).^2)
x, y = rand(CLArrays.CLArray{Float32}, 5), rand(CLArrays.CLArray{Float32}, 2) # Dummy data
loss(x, y)
import Flux
W = Flux.Tracker.param(W)
b = Flux.Tracker.param(b)
l = loss(x, y)
Flux.back!(l)

Here is the output I get. Every line before Flux.back!(l) runs fine. Flux.back!(l) is the first line to give an error.

julia> import CLArrays


julia> W = rand(CLArrays.CLArray{Float32}, 2, 5)
GPU: 2×5 Array{Float32,2}:
 0.267291   0.880699  0.750357  0.631781  0.306915
 0.0219415  0.640799  0.565351  0.29246   0.555488

julia> b = rand(CLArrays.CLArray{Float32}, 2)
GPU: 2-element Array{Float32,1}:
 0.227399
 0.708808

julia> predict(x) = W*x .+ b
predict (generic function with 1 method)

julia> loss(x, y) = sum((predict(x) .- y).^2)
loss (generic function with 1 method)

julia> x, y = rand(CLArrays.CLArray{Float32}, 5), rand(CLArrays.CLArray{Float32}, 2) # Dummy data
(GPU: Float32[0.119538, 0.55785, 0.0553175, 0.0510188, 0.15501], GPU: Float32[0.825204, 0.021798])

julia> loss(x, y)
1.3931789f0

julia> import Flux

julia> W = Flux.Tracker.param(W)
Tracked 2×5 CLArrays.CLArray{Float32,2}:
 0.267291   0.880699  0.750357  0.631781  0.306915
 0.0219415  0.640799  0.565351  0.29246   0.555488

julia> b = Flux.Tracker.param(b)
Tracked 2-element CLArrays.CLArray{Float32,1}:
 0.227399
 0.708808

julia> l = loss(x, y)
1.393179f0 (tracked)

julia> Flux.back!(l)
___________________________________________________________________
Error in Expr rewrite! AssertionError("Found non concrete return type: Tuple{CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}},CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}},Any}")

Expression resulting in the error:
(Core.tuple)((CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 1)::CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 1)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}}, (CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 2)::CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 2)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}}, (CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 3)::RowVector{Float32,CLArrays.CLArray{Float32,1}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 3)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::Any)::Tuple{CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}},CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}},Any}
happening in function tree:
Sugar stack trace:
  [1] CLArrays.reconstruct(Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, Transpiler.CLIntrinsics.GlobalPointer{Float32}, Transpiler.CLIntrinsics.GlobalPointer{Float32}, Transpiler.CLIntrinsics.GlobalPointer{Float32})

  [2] GPUArrays.broadcast_kernel!(CLArrays.KernelState, Flux.Tracker.##41#42, CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}}, Tuple{UInt32,UInt32}, Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}}, Tuple{CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}},CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}})


Code of the context this error occured in:
begin
      return (Core.tuple)((CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 1)::CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 1)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}}, (CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 2)::CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 2)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}}, (CLArrays.reconstruct)((CLArrays.getindex)(x::Tuple{CLArrays.DeviceArray{Float32,2,CLArrays.HostPtr{Float32}},CLArrays.DeviceArray{Float32,1,CLArrays.HostPtr{Float32}},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, 3)::RowVector{Float32,CLArrays.CLArray{Float32,1}}, (CLArrays.getindex)(ptrs::Tuple{Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32},Transpiler.CLIntrinsics.GlobalPointer{Float32}}, 3)::Transpiler.CLIntrinsics.GlobalPointer{Float32})::Any)::Tuple{CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}},CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}},Any}
  end::Any
ERROR: AssertionError: Found non concrete return type: Tuple{CLArrays.DeviceArray{Float32,2,Transpiler.CLIntrinsics.GlobalPointer{Float32}},CLArrays.DeviceArray{Float32,1,Transpiler.CLIntrinsics.GlobalPointer{Float32}},Any}
Stacktrace:
 [1] (::Sugar.##70#78{Sugar.LazyMethod{:CL}})(::Expr) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:562
 [2] replace_or_drop(::Sugar.##70#78{Sugar.LazyMethod{:CL}}, ::Sugar.##19#20, ::Expr, ::Array{Any,1}) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:32
 [3] replace_or_drop(::Function, ::Function, ::Array{Any,1}, ::Array{Any,1}) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:25
 [4] replace_or_drop(::Sugar.##70#78{Sugar.LazyMethod{:CL}}, ::Sugar.##19#20, ::Expr, ::Array{Any,1}) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:44
 [5] replace_or_drop(::Function, ::Function, ::Array{Any,1}, ::Array{Any,1}) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:25
 [6] replace_or_drop(::Sugar.##70#78{Sugar.LazyMethod{:CL}}, ::Sugar.##19#20, ::Expr, ::Array{Any,1}) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:44
 [7] replace_expr(::Function, ::Expr) at /Users/dilum/.julia/v0.6/Sugar/src/ast_tools.jl:21
 [8] rewrite_ast(::Sugar.LazyMethod{:CL}, ::Expr) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:475
 [9] getast!(::Sugar.LazyMethod{:CL}) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:278
 [10] dependencies!(::Sugar.LazyMethod{:CL}, ::Bool) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:664
 [11] dependencies!(::Sugar.LazyMethod{:CL}) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:655
 [12] print_dependencies(::Transpiler.CLIO{Base.AbstractIOBuffer{Array{UInt8,1}}}, ::Sugar.LazyMethod{:CL}, ::Set{Any}) at /Users/dilum/.julia/v0.6/Sugar/src/methods.jl:873
 [13] assemble_kernel(::Sugar.LazyMethod{:CL}) at /Users/dilum/.julia/v0.6/CLArrays/src/compilation.jl:217
 [14] (::CLArrays.##19#21{GPUArrays.#broadcast_kernel!,Tuple{CLArrays.KernelState,Flux.Tracker.##41#42,CLArrays.CLArray{Float32,2},Tuple{UInt32,UInt32},Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}},Tuple{CLArrays.CLArray{Float32,2},CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}},GPUArrays.#broadcast_kernel!,OpenCL.cl.Context})() at /Users/dilum/.julia/v0.6/CLArrays/src/compilation.jl:251
 [15] get!(::CLArrays.##19#21{GPUArrays.#broadcast_kernel!,Tuple{CLArrays.KernelState,Flux.Tracker.##41#42,CLArrays.CLArray{Float32,2},Tuple{UInt32,UInt32},Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}},Tuple{CLArrays.CLArray{Float32,2},CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}},GPUArrays.#broadcast_kernel!,OpenCL.cl.Context}, ::Dict{Any,Any}, ::Tuple{Ptr{Void},GPUArrays.#broadcast_kernel!,NTuple{6,DataType}}) at ./dict.jl:449
 [16] CLArrays.CLFunction(::GPUArrays.#broadcast_kernel!, ::Tuple{CLArrays.KernelState,Flux.Tracker.##41#42,CLArrays.CLArray{Float32,2},Tuple{UInt32,UInt32},Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}},Tuple{CLArrays.CLArray{Float32,2},CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}}, ::OpenCL.cl.Context) at /Users/dilum/.julia/v0.6/CLArrays/src/compilation.jl:249
 [17] _gpu_call(::Function, ::CLArrays.CLArray{Float32,2}, ::Tuple{Flux.Tracker.##41#42,CLArrays.CLArray{Float32,2},Tuple{UInt32,UInt32},Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}},Tuple{CLArrays.CLArray{Float32,2},CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}}, ::Tuple{Tuple{Int64},Tuple{Int64}}) at /Users/dilum/.julia/v0.6/CLArrays/src/compilation.jl:15
 [18] gpu_call(::Function, ::CLArrays.CLArray{Float32,2}, ::Tuple{Flux.Tracker.##41#42,CLArrays.CLArray{Float32,2},Tuple{UInt32,UInt32},Tuple{GPUArrays.BInfo{Array,2},GPUArrays.BInfo{Array,1},GPUArrays.BInfo{Array,2}},Tuple{CLArrays.CLArray{Float32,2},CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}}, ::Int64) at /Users/dilum/.julia/v0.6/GPUArrays/src/abstract_gpu_interface.jl:151
 [19] _broadcast!(::Function, ::CLArrays.CLArray{Float32,2}, ::Tuple{Tuple{Bool,Bool},Tuple{Bool},Tuple{Bool,Bool}}, ::Tuple{Tuple{Int64,Int64},Tuple{Int64},Tuple{Int64,Int64}}, ::CLArrays.CLArray{Float32,2}, ::Tuple{CLArrays.CLArray{Float32,1},RowVector{Float32,CLArrays.CLArray{Float32,1}}}, ::Type{Val{2}}, ::CartesianRange{CartesianIndex{2}}) at /Users/dilum/.julia/v0.6/GPUArrays/src/broadcast.jl:89
 [20] broadcast_c! at ./broadcast.jl:213 [inlined]
 [21] broadcast! at ./broadcast.jl:206 [inlined]
 [22] back(::Base.#*, ::CLArrays.CLArray{Float32,1}, ::TrackedArray{…,CLArrays.CLArray{Float32,2}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/array.jl:316
 [23] back_(::Flux.Tracker.Call{Base.#*,Tuple{TrackedArray{…,CLArrays.CLArray{Float32,2}},CLArrays.CLArray{Float32,1}}}, ::CLArrays.CLArray{Float32,1}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:25
 [24] back(::Flux.Tracker.Tracked{CLArrays.CLArray{Float32,1}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:38
 [25] macro expansion at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:49 [inlined]
 [26] (::Flux.Tracker.##69#71)(::TrackedArray{…,CLArrays.CLArray{Float32,1}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/array.jl:405
 [27] foreach(::Function, ::Tuple{TrackedArray{…,CLArrays.CLArray{Float32,1}},TrackedArray{…,CLArrays.CLArray{Float32,1}}}, ::Tuple{CLArrays.CLArray{Float32,1},CLArrays.CLArray{Float32,1}}, ::Vararg{Tuple{CLArrays.CLArray{Float32,1},CLArrays.CLArray{Float32,1}},N} where N) at ./abstractarray.jl:1734
 [28] back_(::Flux.Tracker.Call{Flux.Tracker.Broadcasted{Base.#+,CLArrays.CLArray{ForwardDiff.Dual{Void,Float32,2},1}},Tuple{TrackedArray{…,CLArrays.CLArray{Float32,1}},TrackedArray{…,CLArrays.CLArray{Float32,1}}}}, ::CLArrays.CLArray{Float32,1}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:25
 [29] back(::Flux.Tracker.Tracked{CLArrays.CLArray{Float32,1}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:38
 [30] macro expansion at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:49 [inlined]
 [31] (::Flux.Tracker.##69#71)(::TrackedArray{…,CLArrays.CLArray{Float32,1}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/array.jl:405
 [32] foreach(::Function, ::Tuple{TrackedArray{…,CLArrays.CLArray{Float32,1}},CLArrays.CLArray{Float32,1}}, ::Tuple{CLArrays.CLArray{Float32,1},CLArrays.CLArray{Float32,1}}, ::Vararg{Tuple{CLArrays.CLArray{Float32,1},CLArrays.CLArray{Float32,1}},N} where N) at ./abstractarray.jl:1734
 [33] back_(::Flux.Tracker.Call{Flux.Tracker.Broadcasted{##1#2,CLArrays.CLArray{ForwardDiff.Dual{Void,Float32,2},1}},Tuple{TrackedArray{…,CLArrays.CLArray{Float32,1}},CLArrays.CLArray{Float32,1}}}, ::CLArrays.CLArray{Float32,1}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:25
 [34] back(::Flux.Tracker.Tracked{CLArrays.CLArray{Float32,1}}, ::CLArrays.CLArray{Float32,1}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:38
 [35] back(::Base.#sum, ::Float32, ::TrackedArray{…,CLArrays.CLArray{Float32,1}}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/array.jl:210
 [36] back_(::Flux.Tracker.Call{Base.#sum,Tuple{TrackedArray{…,CLArrays.CLArray{Float32,1}}}}, ::Float32, ::Float32) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:25
 [37] back(::Flux.Tracker.Tracked{Float32}, ::Int64) at /Users/dilum/.julia/v0.6/Flux/src/tracker/back.jl:36
 [38] back!(::Flux.Tracker.TrackedReal{Float32}) at /Users/dilum/.julia/v0.6/Flux/src/tracker/scalar.jl:14

---

Additional info:

The output of versioninfo() is:

Julia Version 0.6.4
Commit 9d11f62bcb (2018-07-09 19:09 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin14.5.0)
  CPU: Intel(R) Core(TM) i5-4278U CPU @ 2.60GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY Haswell MAX_THREADS=16)
  LAPACK: libopenblas64_
  LIBM: libopenlibm
  LLVM: libLLVM-3.9.1 (ORCJIT, haswell)

The output of Pkg.status() is:

2 required packages:
 - CLArrays                      0.1.3
 - Flux                          0.5.3
39 additional packages:
 - AbstractTrees                 0.1.0
 - Adapt                         0.2.0
 - BinDeps                       0.8.8
 - BinaryProvider                0.3.3
 - CLBLAS                        1.2.0
 - CLFFT                         0.5.2
 - ColorTypes                    0.6.7
 - Colors                        0.8.2
 - CommonSubexpressions          0.1.0
 - Compat                        0.70.0
 - DataFlow                      0.3.1
 - DataStructures                0.8.4
 - DiffResults                   0.0.3
 - DiffRules                     0.0.6
 - FixedPointNumbers             0.4.6
 - ForwardDiff                   0.7.5
 - GPUArrays                     0.2.4
 - GZip                          0.4.0
 - Homebrew                      0.6.3
 - JSON                          0.17.2
 - Juno                          0.4.1
 - Lazy                          0.12.1
 - MacroTools                    0.4.2
 - Matcha                        0.1.1
 - Media                         0.3.0
 - NNlib                         0.3.1
 - NaNMath                       0.3.1
 - Nullables                     0.0.6
 - OpenCL                        0.7.0
 - Primes                        0.3.0
 - Reexport                      0.1.0
 - Requires                      0.4.4
 - SHA                           0.5.7
 - SpecialFunctions              0.6.0
 - StaticArrays                  0.7.2
 - Sugar                         0.4.5
 - Transpiler                    0.4.8
 - URIParser                     0.3.1
 - ZipFile                       0.6.0

[SimonDanisch]

That looks a bit like a problem with RowVector... When I search for RowVector in CLArrays, I realize, that there doesn't seem to be the right converts defined for it... I'll take a look at it!

[DilumAluthge]

Great, thank you Simon!

On Tue, Jul 17, 2018 at 09:57 Simon ***@***.***> wrote: That looks a bit like a problem with RowVector... When I search for RowVector in CLArrays, I realize, that there doesn't seem to be the right converts defined for it... I'll take a look at it! — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#35 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AFXArXOlxD95WbAubkNZx5N4QvTQFa55ks5uHe0tgaJpZM4VR5Ak> .

-- *Dilum Aluthge* *dilum@aluthge.com <dilum@aluthge.com>* *https://www.aluthge.com <https://www.aluthge.com>*

[DilumAluthge]

@SimonDanisch Any luck?