Thread safety of `mul!` in `ToeplitzMatrices.jl` with FFTW plan inside Factorization

General Usage
,
5

Am I right to assume the copyto! is the problem because it modifies the buffer? Reading the buffers should be fine, right?

What I tried now is to modify the mul! function by introducing an option not to reuse the buffer:

function mul!(
    y::StridedVector, A::ToeplitzFactorization, x::StridedVector, α::Number, β::Number; dont_modify_A=false,
)
# ...

    if dont_modify_A
        tmp = copy(A.tmp)
    else
        tmp = A.tmp
    end

# ...

And then it seems to work correctly. However, I’d rather be sure that it has to work correctly…