How many BLAS libraries have this error?

[RonShepard]

@foxtran

After some debugging, I’ve found that the problem is actually gone since MacOS 13.3.

If you mean the Apple accelerate library, the error has persisted up through MacOS 15.7.2. I have not yet upgraded to MacOS 26 on any of my machines. This was reported to Apple in October 2022. I received a response a few weeks later saying that the error would be fixed in a future MacOS and Xcode release. So far, that has not happened.