net/openmpi4 conflicts with net/openmpi. When misc/py-pytorch is installed, a number of other packages are removed because of the conflicts. However, misc/py-pytorch does not use net/openmpi4. USE_MPI requires USE_DISTRIBUTED, and USE_DISTRIBUTED is OFF by default for non-supported platforms (see CMakeLists.txt). The comment in CMakeLists.txt suggests that it will not work. Also, when built with poudriere -t, it is suggested that other LIB_DEPENDS are not necessary as well. Warning: you might not need LIB_DEPENDS on libblis.so Warning: you might not need LIB_DEPENDS on libpthreadpool.so