CI errors on master in LinearAlgebra.mul!

[fredrikekre]

Probably from the mul! PR, cc @tkf

Error in testset LinearAlgebra/addmul:
Test Failed at /buildworker/worker/tester_linux32/build/share/julia/stdlib/v1.3/LinearAlgebra/test/addmul.jl:178
  Expression: ���(collect(returned_mat), collect(�� * A * B + �� * Cc), rtol=rtol)
   Evaluated: [0.6384605169296265] ��� [0.5298598366189116] (rtol=0.0003452669770922512) 

See e.g. https://build.julialang.org/#/builders/13/builds/4527

[tkf]

There are some bug fixes in #32901.

By the way, I realized that the test log is not very helpful since @testset titles are not rendered in the CI. Is there a way to get a similar output as in Pkg.test?

[JeffBezanson]

Hopefully fixed by #32901; can reopen if not.

[vtjnash]

Still seems to be happening (or at least, I assume related), e.g. https://build.julialang.org/#/builders/29/builds/5947/steps/2/logs/stdio

[tkf]

This is probably due to #33743. cc @dkarrasch

Just FYI, to debug this locally (without #32938), comment out this line

julia/stdlib/LinearAlgebra/test/addmul.jl

Line 121 in 6eebbbe

# n_samples = Inf # to try all combinations

and run the file. IIRC, it takes some hours to finish with --compile=min if there is no failure.