gcc -c -I. -I. -I/usr/pkg/include -O -I/usr/pkg/include -fPIE
-fstack-protector-all -D_PATH_SUDOERS=\"/usr/pkg/etc/sudoers\"
-DSUDOERS_UID=0 -DSUDOERS_GID=0 -DS UDOERS_MODE=0440
./ttyname.c
./ttyname.c:1:0: warning: -fPIC ignored for target (all code is position independent) [enabled by default]
 /*
 ^
gcc -o sudo sudo_auth.o getspwuid.o passwd.o exec_pty.o
  get_pty.o iolog.o audit .o boottime.o check.o env.o exec.o
  gettime.o goodpath.o fileops.o find_path.o interfaces.o lbuf.o
  logging.o logwrap.o parse.o parse_args.o set_perms.o sudo.o
  sudo_edit.o sudo_nss.o tgetpass.o ttyname.o -L. -L/usr/pkg/lib
  -Wl,-R/usr/pkg/l ib -pie -fstack-protector-all -lsudo -lz

passwd.o:passwd.c:(.text+0xfd): undefined reference to `crypt'
passwd.o:passwd.c:(.text+0xfd): 
    relocation truncated to fit: R_X86_64_PC32 against undefined symbol `crypt'
passwd.o:passwd.c:(.text+0x111): undefined reference to `crypt'
passwd.o:passwd.c:(.text+0x111): 
    relocation truncated to fit: R_X86_64_PC32 against undefined symbol `crypt'
passwd.o:passwd.c:(.text+0x129): undefined reference to `crypt'
passwd.o:passwd.c:(.text+0x129): 
    relocation truncated to fit: R_X86_64_PC32 against undefined symbol `crypt'
passwd.o:passwd.c:(.text+0x141): undefined reference to `crypt'
passwd.o:passwd.c:(.text+0x141): 
    relocation truncated to fit: R_X86_64_PC32 against undefined symbol `crypt'
/usr/lib/gcc/x86_64-pc-cygwin/4.8.2/../../../../x86_64-pc-cygwin/bin/ld:
passwd.o: bad reloc address 0x0 in section `.pdata'

collect2: error: ld returned 1 exit status
*** Error code 1

Stop.
bmake: stopped in /usr/pkgsrc/security/sudo/work/sudo-1.7.10p7
*** Error code 1

Stop.
bmake: stopped in /usr/pkgsrc/security/sudo
*** Error code 1

Stop.

pty1:makoto@kinu-win7 15:41:46/140124(..security/sudo)% gcc --version
gcc (GCC) 4.8.2
Copyright (C) 2013 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Libs -> libcrypt0 1.1-1 is installed (cygwin)
        libcrypt-devel

Adding libcrypt-devel fixed above problem.