Multithreading message reports too many cores on Mac

[revodavid]

On my Mac, starting 3.2.1 (build 29) gives this message:

Multithreaded BLAS/LAPACK libraries detected. Using 8 cores for math algorithms

However, the System Report says:
Number of Processors: 1
Total Number of Cores: 4

[revodavid]

Fix not required until after 3.2.1 release.

[sfweller]

The RRO is reporting the number of physical and virtual cores here, so in this case the total reported by R is 8 cores.

[richcalaway]

From this post (https://ghc.haskell.org/trac/ghc/ticket/8594), it appears we want to trade our call from sysctl hw.ncpu for sysctl hw.physicalcpu. (Ah, but apparently this is something new in OS X 10.10?)... Maybe we can't use it...Can somebody with a Mac make that modification to their Rprofile.site file and see if it gives the right answer?

[j-martens]

With it, you get the following message:

Multithreaded BLAS/LAPACK libraries detected. Using hw.physicalcpu: 4 cores for math algorithms.

Instead of:
Multithreaded BLAS/LAPACK libraries detected. Using 8 cores for math algorithms.

— Josée