This is a complete mischaracterisation of CMake usage. Today, it's better at portability than most Autotools builds I've used. In projects which maintain both

This is a complete mischaracterisation of CMake usage. Today, it's better at portability than most Autotools builds I've used. In projects which maintain both systems side-by-side, I've had Autotools fail on Solaris, MinGW and Cygwin while with CMake it worked without trouble. And that's for projects which hadn't specifically tested and fixed defects for portability issues on these platforms. Empirically, CMake had better platform coverage. As for the probing of features, take an actual look at what CMake provides. Over an order of magnitude more feature tests. The problem with the Autoconf feature testing is that the vast majority of the tests are 15 years obsolete at this point. The CMake tests are mostly for contemporary platforms. That's where the value lies.