creating this issue for completeness sake, not because change is needed ...

online traffic, e.g. libexpat #55, reveals that CMake adoption can cause a Mach-O library to have versions that differ from the ones produced via Autotools. Apple usually ignores compatibility versions, cf. Siguza, so these discrepancies are often overlooked.

on my obsolete MacBook, Homebrew uses CMake to build libogg 1.3.6 with versions 0.0.0/0.6.8 (compatibility/current). applications like SoX depend on compatibility version 9.0.0, so they are not loaded. the dependency is satisfied when the library is built by Autotools (MacPorts).