Intel Fortran Runtime overwriting Interputs

[LynBar]

Describe the bug 🐞

When the LinearSolve.jl package is imported pressing Ctrl+C no longer throws a SIGINT interrupt, but closes the Julia instance and gives the error
forrtl: error (200): program aborting due to control-C event Initialization of symbol handler failed. Error code %d:87
I fixed this by putting the following in my startup.jl file ENV["FOR_DISABLE_CONSOLE_CTRL_HANDLER"] = "1".

I think this was caused by MKL.jl loading libiomp5 which overwrote the interrupts, though I really don't know much at all about this kind of thing.

FFTW.jl also imports MKL.jl, though I don't get the same problem with that package so I assume the issue is within LinearSolve.jl.

Expected behavior

Ctrl+C throws a SIGINT Interupt.

Minimal Reproducible Example 👇

using LinearSolve
println("precompiled")
while true
    #press Ctrl+C while in loop
end

Error & Stacktrace ⚠️

forrtl: error (200): program aborting due to control-C event
Initialization of symbol handler failed. Error code %d:87

Environment (please complete the following information):

• Output of using Pkg; Pkg.status()

⌃ [7ed4a6bd] LinearSolve v3.26.0

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

  [47edcb42] ADTypes v1.17.0
  [7d9f7c33] Accessors v0.1.42
  [79e6a3ab] Adapt v4.3.0
  [4fba245c] ArrayInterface v7.19.0
  [4c555306] ArrayLayouts v1.11.2
  [d360d2e6] ChainRulesCore v1.26.0
  [38540f10] CommonSolve v0.2.4
  [34da2185] Compat v4.18.0
  [a33af91c] CompositionsBase v0.1.2
  [2569d6c7] ConcreteStructs v0.2.3
  [187b0558] ConstructionBase v1.6.0
  [ffbed154] DocStringExtensions v0.9.5
  [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 v1.7.1
  [ae98c720] Jieko v0.2.1
  [ba0b0d4f] Krylov v0.10.1
  [5078a376] LazyArrays v2.6.2
⌃ [7ed4a6bd] LinearSolve v3.26.0
  [1914dd2f] MacroTools v0.5.16
  [2e0e35c7] Moshi v0.3.7
⌅ [aea7be01] PrecompileTools v1.2.1
  [21216c6a] Preferences v1.5.0
  [3cdcf5f2] RecipesBase v1.3.4
  [731186ca] RecursiveArrayTools v3.37.1
  [189a3867] Reexport v1.2.2
  [ae029012] Requires v1.3.1
  [7e49a35a] RuntimeGeneratedFunctions v0.5.15
⌃ [0bca4576] SciMLBase v2.99.0
⌃ [c0aeaf25] SciMLOperators v0.4.0
  [53ae85a6] SciMLStructures v1.7.0
  [efcf1570] Setfield v1.1.2
  [90137ffa] StaticArrays v1.9.14
  [1e83bf80] StaticArraysCore v1.4.3
  [10745b16] Statistics v1.11.1
  [2efcf032] SymbolicIndexingInterface v0.3.43
  [3a884ed6] UnPack v1.0.2
  [1d5cc7b8] IntelOpenMP_jll v2025.2.0+0
  [856f044c] MKL_jll v2025.2.0+0
  [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

• Output of versioninfo()

Julia Version 1.11.6
Commit 9615af0f26 (2025-07-09 12:58 UTC)
Build Info:
  Official https://julialang.org/ release
Platform Info:
  OS: Windows (x86_64-w64-mingw32)
  CPU: 14 × Intel(R) Core(TM) Ultra 5 125U
  WORD_SIZE: 64
  LLVM: libLLVM-16.0.6 (ORCJIT, alderlake)
Threads: 1 default, 0 interactive, 1 GC (on 14 virtual cores)

Additional context

[ChrisRackauckas]

@jpsamaroo is the kind of person that knows about this stuff?

[jpsamaroo]

This is the unfortunate problem with signals like SIGINT (AKA Ctrl-C) - they're global, and any library can set them to whatever they want, overwriting the previous signal configuration. You might be able to find some environment variable to disable this behavior in the offending library, but if not, we're going to need something like JuliaLang/julia#59147 to allow us to configure signals at runtime.

Also, note that not all code is safely interruptible, so even if we change the signal behavior, Ctrl-C may still cause damage to underlying data structures and corrupt your Julia session or libraries internal state. I don't have a solution to this when talking about external (non-Julia) libraries, so it would be good to document what the behavior of each external library is so that we know what might happen when users hit Ctrl-C during a LinearSolve operation.