Issue with XGBoost.jl and LIBSVM.jl when Julia 1.8.4

General Usage
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Ok, I have a consistent method of “solving” the crash behaviour. It’s not a solution to the bug but I think it may point the way to a means of fixing it.

The basic observation is that the crash doesn’t occur when loading each package’s respective .dll libraries directly (i.e. via a dlopen) but does occur when loading the dll through their respective JuliaBinaryWrappers package (e.g. XGBoost_jll.jl). The common thread linking the examples seems to be:

  1. the wrapper loading aspect,
  2. using CompilerSupportLibraries_jll as a build dependency in the build_tarballs.jl file, e.g:
Dependency("CompilerSupportLibraries_jll"; platforms=filter(!Sys.isbsd, platforms))
  1. and the use of OpenMP / GOMP / libgomp-1.dll within the wrapper C library.

So a method of “solving” the crash is to run the following before loading the package:

## "Solution" code:
import CompilerSupportLibraries_jll
using Libdl
dlclose(CompilerSupportLibraries_jll.libgomp_handle)

I’ve verified that this works for me with the following reproducible crash MWEs given here and in linked issues:

XGBoost.jl 
using XGBoost
(X, y) = (randn(100,4), randn(100))
bst = xgboost((X, y), num_round=5, max_depth=6, objective="reg:squarederror")
LIBSVM.jl 
# LIBSVM.jl (https://github.com/JuliaML/LIBSVM.jl/issues/95#issue-1517938994)
using LIBSVM
(X, y) = (randn(100,4), randn(100))
svmtrain(X', y)
BLIS.jl 
# (https://github.com/JuliaLinearAlgebra/BLIS.jl/issues/23#issuecomment-1515754372)

using blis_jll
using LinearAlgebra
BLAS.lbt_find_backing_library("dgemm_", :ilp64)  # for information
BLAS.lbt_forward(blis_jll.blis_path; clear=false, verbose=true)
BLAS.lbt_find_backing_library("dgemm_", :ilp64) # for information
A = rand(10,5); B = rand(5,8);
A * B

I guess the question now is why is the above “solution” effective?

It seems to be reverting or unloading the default libgomp, possibly to a system version? I get the fallback dllist() loading

"C:\\ProgramData\\Anaconda3\\Library\\mingw-w64\\bin\\libgomp-1.dll"

Is it working because otherwise there is some incompatibility with a GCC 12 version that julia 1.8.4 and above is loading by default?

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