bug#63986: Julia is very slow

[Simon Tournier]

Hi Efraim,

Applying the patch is done in v3 of #66030.

    https://issues.guix.gnu.org/issue/66030

and QA processed all.

    https://qa.guix.gnu.org/issue/66030/

It is almost good except one strong annoyance [1]@

--8<---------------cut here---------------start------------->8---
Singular value decomposition |   57     57  5.0s
Hermitian: Error During Test at 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/rectfullpacked.jl:12
  Got exception outside of a @test
  could not load symbol "dsfrk_64_":
  
/gnu/store/h5mgc7ar7a05f9rwrd1makhzays5wd3s-julia-1.8.3/bin/../lib/julia/liblapack.so:
 undefined symbol: dsfrk_64_
  Stacktrace:
    [1] sfrk!(transr::Char, uplo::Char, trans::Char, alpha::Float64, 
A::Matrix{Float64}, beta::Float64, C::Vector{Float64})
      @ GenericLinearAlgebra.LAPACK2 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/src/lapack.jl:523
    [2] Ac_mul_A_RFP(A::Matrix{Float64}, uplo::Symbol)
      @ GenericLinearAlgebra 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/src/rectfullpacked.jl:77
    [3] macro expansion
      @ 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/rectfullpacked.jl:13
 [inlined]
    [4] macro expansion
      @ 
/gnu/store/h5mgc7ar7a05f9rwrd1makhzays5wd3s-julia-1.8.3/share/julia/stdlib/v1.8/Test/src/Test.jl:1360
 [inlined]
    [5] macro expansion
      @ 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/rectfullpacked.jl:13
 [inlined]
    [6] macro expansion
      @ 
/gnu/store/h5mgc7ar7a05f9rwrd1makhzays5wd3s-julia-1.8.3/share/julia/stdlib/v1.8/Test/src/Test.jl:1436
 [inlined]
    [7] macro expansion
      @ 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/rectfullpacked.jl:7
 [inlined]
    [8] macro expansion
      @ 
/gnu/store/h5mgc7ar7a05f9rwrd1makhzays5wd3s-julia-1.8.3/share/julia/stdlib/v1.8/Test/src/Test.jl:1360
 [inlined]
    [9] top-level scope
      @ 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/rectfullpacked.jl:7
   [10] include(fname::String)
      @ Base.MainInclude ./client.jl:476
   [11] top-level scope
      @ 
/gnu/store/zkx6p7kz3m5k5w5iy0l1d09b2n8b0ib3-julia-genericlinearalgebra-0.2.5/share/julia/loadpath/GenericLinearAlgebra/test/runtests.jl:10
   [12] include(mod::Module, _path::String)
      @ Base ./Base.jl:419
   [13] exec_options(opts::Base.JLOptions)
      @ Base ./client.jl:303
   [14] _start()
      @ Base ./client.jl:522
--8<---------------cut here---------------end--------------->8---

Any idea?  I have no idea and it is blocking the merge because ~20
packages are then broken.  Well, if we have no idea, I will push the fix
for “Julia is slow” and we will fix later these ~20 failures.  WDYT?

Cheers,
simon

1: https://bordeaux.guix.gnu.org/build/30e3aaec-dbde-423b-9554-67a64881e0cf/log