# use common ARM7 periph code USEMODULE += arm7_common_periph ifneq (,$(filter picolibc,$(FEATURES_USED))) # Use Picolibc when explicitly selected USEMODULE += picolibc else # all cortex MCU's use newlib as libc USEMODULE += newlib # use the nano-specs of Newlib when available USEMODULE += newlib_nano endif