`solution_summary` issue on 32-bit platforms (x86 linux)

[franckgaga]

I cannot provide a MRE since I don't own a 32-bit computer, but I started doing CI on 32-bit platforms and ModelPredictiveControl.getinfo fails because JuMP.solution_summary crashes on linux x86. See the log here (it's presumably related to Int pointing to Int32, typically easy to solve):

https://github.com/JuliaControl/ModelPredictiveControl.jl/actions/runs/33441325758/job/99650021204#step:9:339

[franckgaga]

I'm not 100% sure, but it's possible that it's not an issue on MOI.jl side, but on DAQP.jl, the solver used for this specific test.

[araujoms]

Can't you install a 32-bit operating system on a virtual machine? Otherwise debugging is very difficult.

[franckgaga]

Yes I can, good point I did not thought of this. I will try this and get back with a clearer MRE and stacktrace.

[franckgaga]

Okay, I created this MRE an ran it on VM with Ubuntu 16 32-bit (I just learned that most Linux distro does not support 32-bit anymore, I'm putting way too much efforts for a platform that is almost dead...):

using ModelPredictiveControl, JuMP, DAQP, OSQP, LinearAlgebra, ControlSystemsBase

Ts = 400.0
sys = [ tf(1.90,[1800.0,1])   tf(1.90,[1800.0,1])   tf(1.90,[1800.0,1]);
        tf(-0.74,[800.0,1])   tf(0.74,[800.0,1])    tf(-0.74,[800.0,1])   ] 
linmodel = LinModel(sys,Ts,i_u=[1,2], i_d=[3])
linmodel = setop!(linmodel, uop=[10,50], yop=[50,30], dop=[5])

Q̂ = diagm([1/4, 1/4, 1/4, 1/4].^2) 
R̂ = diagm([1, 1].^2)
optim = Model(DAQP.Optimizer) # Model(OSQP.Optimizer)
covestim = SteadyKalmanFilter(linmodel, 1:2, 0, 0, Q̂, R̂)
P̂_0 = covestim.cov.P̂
mhe3 = MovingHorizonEstimator(linmodel, 2, 1:2, 0, 0, P̂_0, Q̂, R̂; optim, covestim)
preparestate!(mhe3, [50, 30], [5])
info = getinfo(mhe3)

It crashes with DAQP but not with OSQP so this is presumably a bug on DAQP side. The error is:

ERROR: LoadError: TypeError: in typeassert, expected Int32, got a value of type Int64
Stacktrace:
  [1] _get_model_attribute(model::MathOptInterface.Utilities.CachingOptimizer{…}, attr::MathOptInterface.ResultCount)
    @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/13jDB/src/Utilities/cachingoptimizer.jl:862
  [2] get(model::MathOptInterface.Utilities.CachingOptimizer{…}, attr::MathOptInterface.ResultCount)
    @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/13jDB/src/Utilities/cachingoptimizer.jl:897
  [3] get(b::MathOptInterface.Bridges.LazyBridgeOptimizer{…}, attr::MathOptInterface.ResultCount)
    @ MathOptInterface.Bridges ~/.julia/packages/MathOptInterface/13jDB/src/Bridges/bridge_optimizer.jl:1038
  [4] _get_model_attribute(model::MathOptInterface.Utilities.CachingOptimizer{…}, attr::MathOptInterface.ResultCount)
    @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/13jDB/src/Utilities/cachingoptimizer.jl:862
  [5] get(model::MathOptInterface.Utilities.CachingOptimizer{…}, attr::MathOptInterface.ResultCount)
    @ MathOptInterface.Utilities ~/.julia/packages/MathOptInterface/13jDB/src/Utilities/cachingoptimizer.jl:897
  [6] _moi_get_result(model::MathOptInterface.Utilities.CachingOptimizer{…}, args::MathOptInterface.ResultCount)
    @ JuMP ~/.julia/packages/JuMP/Y8Mtc/src/optimizer_interface.jl:1257
  [7] get(model::Model, attr::MathOptInterface.ResultCount)
    @ JuMP ~/.julia/packages/JuMP/Y8Mtc/src/optimizer_interface.jl:1277
  [8] result_count(model::Model)
    @ JuMP ~/.julia/packages/JuMP/Y8Mtc/src/optimizer_interface.jl:820
  [9] solution_summary(model::Model; result::Int32, verbose::Bool)
    @ JuMP ~/.julia/packages/JuMP/Y8Mtc/src/solution_summary.jl:92
 [10] solution_summary
    @ ~/.julia/packages/JuMP/Y8Mtc/src/solution_summary.jl:87 [inlined]
 [11] getinfo(estim::MovingHorizonEstimator{…})
    @ ModelPredictiveControl ~/.julia/packages/ModelPredictiveControl/cJ6gF/src/estimator/mhe/execute.jl:187
 [12] top-level scope
    @ ~/Documents/project/src/debug_32bit.jl:16
 [13] include(mapexpr::Function, mod::Module, _path::String)
    @ Base ./Base.jl:307
 [14] top-level scope
    @ REPL[6]:1
in expression starting at /home/francis/Documents/project/src/debug_32bit.jl:16
Some type information was truncated. Use `show(err)` to see complete types.

Sorry for the noise.