m .+= ...
causes a data race. Every thread tries to update every element in m
.
If you need a parallel sum, checkout Folds.sum
or FLoops.@reduce
.
This is not possible at the moment. It’d require a rather large surgery to the Julia runtime.
You’d need @floop ThreadedEx() for i in 1:size(x, 1)
. Similar Q/A Problem with `@reduce` of `FLoops`; data race? - #2 by tkf