if 'RISCV' not in config.root.targets:
    config.unsupported = True

flags64 = '--target=riscv64 -nostdlib -ffreestanding -Wl,--emit-relocs'
flags32 = '--target=riscv32 -march=rv32imac -mabi=ilp32 -nostdlib -ffreestanding -Wl,--emit-relocs'

config.substitutions.insert(0, ('%cflags64', f'%cflags {flags64}'))
config.substitutions.insert(0, ('%cflags32', f'%cflags {flags32}'))
config.substitutions.insert(0, ('%cxxflags64', f'%cxxflags {flags64}'))
config.substitutions.insert(0, ('%cxxflags32', f'%cxxflags {flags32}'))