`remake` is broken for `remake(::LinearProblem, u0 = new_u0)`

[jClugstor]

Describe the bug 🐞

remake does not work when trying to remake u0 of a LinearProblem.

Expected behavior

remake with u0 on a LinearProblem should return a problem with the update u0.

Minimal Reproducible Example 👇

julia> using LinearSolve

julia> prob = LinearProblem(rand(3,3), rand(3), u0 = rand(3))
LinearProblem. In-place: true
b: 3-element Vector{Float64}:
 0.6316773602981235
 0.433928832099021
 0.6622619036470172

julia> remake(prob, u0 = rand(3))

Error & Stacktrace ⚠️

julia> remake(prob, u0 = rand(3))
ERROR: type LinearProblem has no field f
Stacktrace:
 [1] getproperty
   @ ~/.julia/packages/SciMLBase/iHgIu/src/problems/problem_interface.jl:5 [inlined]
 [2] updated_u0_p(prob::LinearProblem{…}, u0::Vector{…}, p::Missing, t0::Nothing; interpret_symbolicmap::Bool, use_defaults::Bool)
   @ SciMLBase ~/.julia/packages/SciMLBase/iHgIu/src/remake.jl:1152
 [3] remake(prob::LinearProblem{…}; u0::Vector{…}, p::Missing, interpret_symbolicmap::Bool, use_defaults::Bool, kwargs::@Kwargs{})
   @ SciMLBase ~/.julia/packages/SciMLBase/iHgIu/src/remake.jl:82
 [4] top-level scope
   @ REPL[8]:1
Some type information was truncated. Use `show(err)` to see complete types.

Environment (please complete the following information):

• Output of using Pkg; Pkg.status()

(jl_3LgfLK) pkg> st
Status `/tmp/jl_3LgfLK/Project.toml`
  [7ed4a6bd] LinearSolve v3.16.0

• Output of using Pkg; Pkg.status(; mode = PKGMODE_MANIFEST)

(jl_3LgfLK) pkg> st -m
Status `/tmp/jl_3LgfLK/Manifest.toml`
  [47edcb42] ADTypes v1.14.0
  [7d9f7c33] Accessors v0.1.42
  [79e6a3ab] Adapt v4.3.0
  [4fba245c] ArrayInterface v7.19.0
  [4c555306] ArrayLayouts v1.11.1
  [d360d2e6] ChainRulesCore v1.25.1
  [38540f10] CommonSolve v0.2.4
  [34da2185] Compat v4.16.0
  [a33af91c] CompositionsBase v0.1.2
  [2569d6c7] ConcreteStructs v0.2.3
  [187b0558] ConstructionBase v1.5.8
  [a8cc5b0e] Crayons v4.1.1
  [9a962f9c] DataAPI v1.16.0
  [e2d170a0] DataValueInterfaces v1.0.0
  [ffbed154] DocStringExtensions v0.9.4
  [4e289a0a] EnumX v1.0.5
  [e2ba6199] ExprTools v0.1.10
  [55351af7] ExproniconLite v0.10.14
  [1a297f60] FillArrays v1.13.0
  [069b7b12] FunctionWrappers v1.1.3
  [77dc65aa] FunctionWrappersWrappers v0.1.3
  [46192b85] GPUArraysCore v0.2.0
  [3587e190] InverseFunctions v0.1.17
  [82899510] IteratorInterfaceExtensions v1.0.0
  [692b3bcd] JLLWrappers v1.7.0
  [ae98c720] Jieko v0.2.1
  [ba0b0d4f] Krylov v0.10.1
  [b964fa9f] LaTeXStrings v1.4.0
  [5078a376] LazyArrays v2.6.1
  [7ed4a6bd] LinearSolve v3.16.0
  [1914dd2f] MacroTools v0.5.16
  [2e0e35c7] Moshi v0.3.5
  [bac558e1] OrderedCollections v1.8.1
⌅ [aea7be01] PrecompileTools v1.2.1
  [21216c6a] Preferences v1.4.3
  [08abe8d2] PrettyTables v2.4.0
  [3cdcf5f2] RecipesBase v1.3.4
  [731186ca] RecursiveArrayTools v3.33.0
  [189a3867] Reexport v1.2.2
  [ae029012] Requires v1.3.1
  [7e49a35a] RuntimeGeneratedFunctions v0.5.15
  [0bca4576] SciMLBase v2.96.0
  [c0aeaf25] SciMLOperators v1.3.1
  [53ae85a6] SciMLStructures v1.7.0
  [efcf1570] Setfield v1.1.2
  [1e83bf80] StaticArraysCore v1.4.3
  [10745b16] Statistics v1.11.1
  [892a3eda] StringManipulation v0.4.1
  [2efcf032] SymbolicIndexingInterface v0.3.40
  [3783bdb8] TableTraits v1.0.1
  [bd369af6] Tables v1.12.1
  [3a884ed6] UnPack v1.0.2
  [1d5cc7b8] IntelOpenMP_jll v2025.0.4+0
  [856f044c] MKL_jll v2025.0.1+1
  [1317d2d5] oneTBB_jll v2022.0.0+0
  [0dad84c5] ArgTools v1.1.2
  [56f22d72] Artifacts v1.11.0
  [2a0f44e3] Base64 v1.11.0
  [ade2ca70] Dates v1.11.0
  [8ba89e20] Distributed v1.11.0
  [f43a241f] Downloads v1.6.0
  [7b1f6079] FileWatching v1.11.0
  [9fa8497b] Future v1.11.0
  [b77e0a4c] InteractiveUtils v1.11.0
  [4af54fe1] LazyArtifacts v1.11.0
  [b27032c2] LibCURL v0.6.4
  [76f85450] LibGit2 v1.11.0
  [8f399da3] Libdl v1.11.0
  [37e2e46d] LinearAlgebra v1.11.0
  [56ddb016] Logging v1.11.0
  [d6f4376e] Markdown v1.11.0
  [ca575930] NetworkOptions v1.2.0
  [44cfe95a] Pkg v1.11.0
  [de0858da] Printf v1.11.0
  [9a3f8284] Random v1.11.0
  [ea8e919c] SHA v0.7.0
  [9e88b42a] Serialization v1.11.0
  [6462fe0b] Sockets v1.11.0
  [2f01184e] SparseArrays v1.11.0
  [fa267f1f] TOML v1.0.3
  [a4e569a6] Tar v1.10.0
  [cf7118a7] UUIDs v1.11.0
  [4ec0a83e] Unicode v1.11.0
  [e66e0078] CompilerSupportLibraries_jll v1.1.1+0
  [deac9b47] LibCURL_jll v8.6.0+0
  [e37daf67] LibGit2_jll v1.7.2+0
  [29816b5a] LibSSH2_jll v1.11.0+1
  [c8ffd9c3] MbedTLS_jll v2.28.6+0
  [14a3606d] MozillaCACerts_jll v2023.12.12
  [4536629a] OpenBLAS_jll v0.3.27+1
  [bea87d4a] SuiteSparse_jll v7.7.0+0
  [83775a58] Zlib_jll v1.2.13+1
  [8e850b90] libblastrampoline_jll v5.11.0+0
  [8e850ede] nghttp2_jll v1.59.0+0
  [3f19e933] p7zip_jll v17.4.0+2
Info Packages marked with ⌅ have new versions available but compatibility constraints restrict them from upgrading. To see why use `status --outdated -m`

• Output of versioninfo()

julia> versioninfo()
Julia Version 1.11.3
Commit d63adeda50d (2025-01-21 19:42 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Linux (x86_64-linux-gnu)
  CPU: 16 × AMD Ryzen 7 6800U with Radeon Graphics
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, znver3)
Threads: 1 default, 0 interactive, 1 GC (on 16 virtual cores)

[AayushSabharwal]

Fixed in SciML/SciMLBase.jl#1046

[jClugstor]

I still can't remake with u0.

julia> using LinearSolve

julia> A = rand(3,3)
3×3 Matrix{Float64}:
 0.229799  0.880254  0.116142
 0.993389  0.83134   0.97744
 0.36278   0.915723  0.83153

julia> b = rand(3)
3-element Vector{Float64}:
 0.535551350834677
 0.48195928465257876
 0.5263335323269414

julia> prob = LinearProblem(A,b)
LinearProblem. In-place: true
b: 3-element Vector{Float64}:
 0.535551350834677
 0.48195928465257876
 0.5263335323269414

julia> remake(prob, u0 = rand(3))
ERROR: MethodError: no method matching has_sys(::Nothing)
The function `has_sys` exists, but no method is defined for this combination of argument types.

Closest candidates are:
  has_sys(::SciMLBase.SymbolicLinearInterface)
   @ SciMLBase ~/.julia/packages/SciMLBase/l0G2E/src/problems/linear_problems.jl:30
  has_sys(::HomotopyNonlinearFunction)
   @ SciMLBase ~/.julia/packages/SciMLBase/l0G2E/src/scimlfunctions.jl:5046
  has_sys(::SciMLBase.AbstractSciMLFunction)
   @ SciMLBase ~/.julia/packages/SciMLBase/l0G2E/src/scimlfunctions.jl:4951

Stacktrace:
 [1] updated_u0_p(prob::LinearProblem{…}, u0::Vector{…}, p::Missing, t0::Nothing; interpret_symbolicmap::Bool, use_defaults::Bool)
   @ SciMLBase ~/.julia/packages/SciMLBase/l0G2E/src/remake.jl:1154
 [2] remake(prob::LinearProblem{…}; u0::Vector{…}, p::Missing, interpret_symbolicmap::Bool, use_defaults::Bool, kwargs::@Kwargs{})
   @ SciMLBase ~/.julia/packages/SciMLBase/l0G2E/src/remake.jl:82
 [3] top-level scope
   @ REPL[20]:1
Some type information was truncated. Use `show(err)` to see complete types.

(jl_Mvgmtf) pkg> st
Status `/tmp/jl_Mvgmtf/Project.toml`
  [7ed4a6bd] LinearSolve v3.17.0
  [0bca4576] SciMLBase v2.98.0