I installed libgccjit from homebrew on the latest MacOS. Using the option --with-native-compilation to build Emacs, during the configure phase I got: checking libgccjit.h usability... yes checking libgccjit.h presence... yes checking for libgccjit.h... yes configure: error: Installed libgccjit has failed passing the smoke test. “usabilty” yes, but then “failed” some test, look contradictory. What is the “smoke test”? There is no hint in any of the docs coming with Emacs. Konrad