../util-linux-2.28.1/schedutils/chrt.c:88:17: error: ‘__NR_sched_setattr’ undeclared (first use in this function)

Question

i am trying to build os-image using bitbake in yocto project. i got the following error.

../util-linux-2.28.1/schedutils/chrt.c:88:17: error: ‘__NR_sched_setattr’ undeclared (first use in this function)

i followed the instructions given in Mega Manual of yocto. how to resolve this build error?

Answer 1

This type of error messages appear when some user space program or library is being built for kernel that doesn't support some system call, sched_setattr in this case. Either you build on very old linux (appeared in 3.14) or which is most probable the arch you are building on doesn't support this system call (you haven't specified which arch you are building on, so I cannot check).

Either way, it's possible to disable this particular part of util-linux with configuration option --disable-schedutils. You won't get chrt, ionice, taskset (process manipulation) tools on your device in this case but they are probably not very useful for you.

In yocto build environment, you can first modify recipe for util-linux, well actually include file for recipe (meta/recipes-core/util-linux/util-linux.inc), by adding one line:

SHARED_EXTRA_OECONF = "--disable-use-tty-group \
                       --disable-makeinstall-chown \
... 
                       --disable-schedutils \
"

and check if it works for you. Later you can add

EXTRA_OECONF_append_util-linux = " --disable-schedutils" 

to your conf/local.conf or to util-linux bbappend file in your working meta layer (if you have it).

Answer 2

It's probably finding ncurses headers from your host machine when it should only be looking in the Yocto sysroot. There's a patch that fixes this, it will probably end up in master soon. Either use the patch locally for now or as a workaround remove libncurses6 and libncursesw6 development packages from your build host.