Guix, As I read the source, cmake-build-system should by default both build and check with parallelism enabled. When I locally build a package only the build phase runs with parallelism and tests are being run in serial.
When I run a manual build (stopping an in-process build run with '-K', then removing all files under the build directory, then copying and running the commands from the stopped build) I do not see a parallel build, nor do I see any parallelism passed by command or environment arguments (no '-j' or CMAKE_BUILD_PARALLEL_LEVEL). If this has been previously discussed please direct me to the earlier discussion. Often my builds are fast (running in parallel) but tests are slow (running in serial) and I am puzzled why any of this works the way it does. Greg
