make[3]: Entering directory '/home/seven/lede/build_dir/target-mips_24kc_musl/busybox-1.28.3'
  ...
  CC      util-linux/setsid.o
  CC      util-linux/swaponoff.o
  CC      util-linux/switch_root.o
  CC      util-linux/taskset.o
  CC      util-linux/uevent.o
  CC      util-linux/umount.o
  CC      util-linux/wall.o
  AR      util-linux/lib.a
  LD      util-linux/volume_id/built-in.o
  CC      util-linux/volume_id/exfat.o
  CC      util-linux/volume_id/ext.o
  CC      util-linux/volume_id/fat.o
  CC      util-linux/volume_id/get_devname.o
  CC      util-linux/volume_id/iso9660.o
  CC      util-linux/volume_id/linux_swap.o
  CC      util-linux/volume_id/ntfs.o
  CC      util-linux/volume_id/util.o
  CC      util-linux/volume_id/volume_id.o
  AR      util-linux/volume_id/lib.a
  LINK    busybox_unstripped
Trying libraries: crypt m
Failed: -Wl,--start-group  -lcrypt -lm  -Wl,--end-group
Output of:
mips-openwrt-linux-musl-gcc -Wall -Wshadow -Wwrite-strings -Wundef -Wstrict-prototypes -Wunused -Wunused-parameter -Wunused-function -Wunused-value -Wmissing-prototypes -Wmissing-declarations -Wno-format-security -Wdeclaration-after-statement -Wold-style-definition -fno-builtin-strlen -finline-limit=0 -fomit-frame-pointer -ffunction-sections -fdata-sections -fno-guess-branch-probability -funsigned-char -falign-functions=1 -falign-jumps=1 -falign-labels=1 -falign-loops=1 -fno-unwind-tables -fno-asynchronous-unwind-tables -fno-builtin-printf -Os -L/home/seven/lede/staging_dir/target-mips_24kc_musl/usr/lib -L/home/seven/lede/staging_dir/target-mips_24kc_musl/lib -L/home/seven/lede/staging_dir/toolchain-mips_24kc_gcc-7.3.0_musl/usr/lib -L/home/seven/lede/staging_dir/toolchain-mips_24kc_gcc-7.3.0_musl/lib -znow -zrelro -o busybox_unstripped -Wl,--sort-common -Wl,--sort-section,alignment -Wl,--gc-sections -Wl,--start-group applets/built-in.o archival/lib.a archival/libarchive/lib.a console-tools/lib.a coreutils/lib.a coreutils/libcoreutils/lib.a debianutils/lib.a klibc-utils/lib.a e2fsprogs/lib.a editors/lib.a findutils/lib.a init/lib.a libbb/lib.a libpwdgrp/lib.a loginutils/lib.a mailutils/lib.a miscutils/lib.a modutils/lib.a networking/lib.a networking/libiproute/lib.a networking/udhcp/lib.a printutils/lib.a procps/lib.a runit/lib.a selinux/lib.a shell/lib.a sysklogd/lib.a util-linux/lib.a util-linux/volume_id/lib.a archival/built-in.o archival/libarchive/built-in.o console-tools/built-in.o coreutils/built-in.o coreutils/libcoreutils/built-in.o debianutils/built-in.o klibc-utils/built-in.o e2fsprogs/built-in.o editors/built-in.o findutils/built-in.o init/built-in.o libbb/built-in.o libpwdgrp/built-in.o loginutils/built-in.o mailutils/built-in.o miscutils/built-in.o modutils/built-in.o networking/built-in.o networking/libiproute/built-in.o networking/udhcp/built-in.o printutils/built-in.o procps/built-in.o runit/built-in.o selinux/built-in.o shell/built-in.o sysklogd/built-in.o util-linux/built-in.o util-linux/volume_id/built-in.o -Wl,--end-group -Wl,--start-group -lcrypt -lm -Wl,--end-group
==========
util-linux/lib.a(mount.o): In function `xdr_fhstatus':
mount.c:(.text.xdr_fhstatus+0x4): undefined reference to `xdr_u_int'
mount.c:(.text.xdr_fhstatus+0x14): undefined reference to `xdr_opaque'
util-linux/lib.a(mount.o): In function `xdr_mountres3':
mount.c:(.text.xdr_mountres3+0x4): undefined reference to `xdr_enum'
mount.c:(.text.xdr_mountres3+0x1e): undefined reference to `xdr_bytes'
mount.c:(.text.xdr_mountres3+0x3a): undefined reference to `xdr_array'
mount.c:(.text.xdr_mountres3+0x48): undefined reference to `xdr_int'
util-linux/lib.a(mount.o): In function `xdr_dirpath':
mount.c:(.text.xdr_dirpath+0x6): undefined reference to `xdr_string'
util-linux/lib.a(mount.o): In function `__jend_nfsmount_243':
mount.c:(.text.nfsmount+0x552): undefined reference to `pmap_getmaps'
mount.c:(.text.nfsmount+0x5d0): undefined reference to `clntudp_create'
mount.c:(.text.nfsmount+0x5fc): undefined reference to `clnttcp_create'
mount.c:(.text.nfsmount+0x616): undefined reference to `clnt_spcreateerror'
mount.c:(.text.nfsmount+0x71e): undefined reference to `authunix_create_default'
mount.c:(.text.nfsmount+0x766): undefined reference to `clnt_sperror'
mount.c:(.text.nfsmount+0x782): undefined reference to `clnt_sperror'
util-linux/lib.a(mount.o): In function `__pend_nfsmount_494':
mount.c:(.text.nfsmount+0x910): undefined reference to `bindresvport'
mount.c:(.text.nfsmount+0x93a): undefined reference to `pmap_getport'
collect2: error: ld returned 1 exit status
Note: if build needs additional libraries, put them in CONFIG_EXTRA_LDLIBS.
Example: CONFIG_EXTRA_LDLIBS="pthread dl tirpc audit pam"
Makefile:718: recipe for target 'busybox_unstripped' failed
make[3]: *** [busybox_unstripped] Error 1
make[3]: Leaving directory '/home/seven/lede/build_dir/target-mips_24kc_musl/busybox-1.28.3'
Makefile:118: recipe for target '/home/seven/lede/build_dir/target-mips_24kc_musl/busybox-1.28.3/.built' failed
make[2]: *** [/home/seven/lede/build_dir/target-mips_24kc_musl/busybox-1.28.3/.built] Error 2
make[2]: Leaving directory '/home/seven/lede/package/utils/busybox'
Command exited with non-zero status 2
time: package/utils/busybox/compile#2.70#1.49#4.94
package/Makefile:107: recipe for target 'package/utils/busybox/compile' failed
make[1]: *** [package/utils/busybox/compile] Error 2
make[1]: Leaving directory '/home/seven/lede'
/home/seven/lede/include/toplevel.mk:216: recipe for target 'package/utils/busybox/compile' failed
make: *** [package/utils/busybox/compile] Error 2