NetBSD/macppc (8.0) で pkgsrc/www/apache24 が作れない問題

/.../libapr-1.so: undefined reference to `__sync_fetch_and_add_8'
/.../libapr-1.so: undefined reference to `__sync_val_compare_and_swap_8'
/.../libapr-1.so: undefined reference to `__sync_lock_test_and_set_8'
/.../libapr-1.so: undefined reference to `__sync_fetch_and_sub_8'
/.../libapr-1.so: undefined reference to `__sync_sub_and_fetch_8'

……というエラーが出る。