GNU Make is widely used, and actively maintained. New features are added regularly. It's the build tool targeted by Kconfig (used in the Linux kernel and elsewh

GNU Make is widely used, and actively maintained. New features are added regularly. It's the build tool targeted by Kconfig (used in the Linux kernel and elsewhere), and also it's probably true to call it CMake's most common backend. So, don't worry - GNU Make isn't going anywhere, regardless of what eventually happens to Autoconf.