In /usr/bin/dev_debug_vboot line 15:
[ "${EUID:-0}" = 0 ] && PATH=/bin:/sbin:/usr/bin:/usr/sbin
   ^--------^ SC2039: In POSIX sh, EUID is undefined.


In /usr/bin/dev_debug_vboot line 34:
  local prog
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 88:
  echo -n "$@"
       ^-- SC2039: In POSIX sh, echo flags are undefined.


In /usr/bin/dev_debug_vboot line 121:
  local missing
  ^-----------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 124:
  for tool in $* ; do
              ^-- SC2048: Use "$@" (with quotes) to prevent whitespace problems.


In /usr/bin/dev_debug_vboot line 135:
  local start
  ^---------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 136:
  local size
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 137:
  local part
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 138:
  local rest
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 142:
    while read start size part rest; do
          ^--^ SC2162: read without -r will mangle backslashes.


In /usr/bin/dev_debug_vboot line 144:
      log dd if="$1" bs=512 skip=${start} count=${size} of="${name}" &&
                                 ^------^ SC2086: Double quote to prevent globbing and word splitting.
                                                ^-----^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
      log dd if="$1" bs=512 skip="${start}" count="${size}" of="${name}" &&


In /usr/bin/dev_debug_vboot line 150:
  local a
  ^-----^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 151:
  local b
  ^-----^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 152:
  local what
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 153:
  local num
  ^-------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 154:
  local rest
  ^--------^ SC2039: In POSIX sh, 'local' is undefined.


In /usr/bin/dev_debug_vboot line 156:
  a='/(Data|Kernel) key version/ {print $1,$4}'
    ^-- SC2016: Expressions don't expand in single quotes, use double quotes for that.


In /usr/bin/dev_debug_vboot line 157:
  b='/Kernel version/ {print $1, $3}'
    ^-- SC2016: Expressions don't expand in single quotes, use double quotes for that.


In /usr/bin/dev_debug_vboot line 158:
  awk "$a $b" "$1" | while read what num rest; do
                           ^--^ SC2162: read without -r will mangle backslashes.


In /usr/bin/dev_debug_vboot line 183:
[ -f /etc/default/vboot_reference ] && . /etc/default/vboot_reference
                                         ^--------------------------^ SC1091: Not following: /etc/default/vboot_reference was not specified as input (see shellcheck -x).


In /usr/bin/dev_debug_vboot line 187:
       -n $0 -- "$@")
          ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
       -n "$0" -- "$@")


In /usr/bin/dev_debug_vboot line 239:
  [ -d ${TMPDIR} ] || die "$TMPDIR doesn't exist"
       ^-------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
  [ -d "${TMPDIR}" ] || die "$TMPDIR doesn't exist"


In /usr/bin/dev_debug_vboot line 244:
[ -d ${TMPDIR} ] || mkdir -p ${TMPDIR} || exit 1
     ^-------^ SC2086: Double quote to prevent globbing and word splitting.
                             ^-------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
[ -d "${TMPDIR}" ] || mkdir -p "${TMPDIR}" || exit 1


In /usr/bin/dev_debug_vboot line 245:
cd ${TMPDIR} || exit 1
   ^-------^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
cd "${TMPDIR}" || exit 1


In /usr/bin/dev_debug_vboot line 268:
require_utils $need
              ^---^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
require_utils "$need"


In /usr/bin/dev_debug_vboot line 279:
  log cgpt show $d
                ^-- SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
  log cgpt show "$d"


In /usr/bin/dev_debug_vboot line 384:
  kc=$(expr $kc + 1)
       ^--^ SC2003: expr is antiquated. Consider rewriting this using $((..)), ${} or [[ ]].

For more information:
  https://www.shellcheck.net/wiki/SC2039 -- In POSIX sh, 'local' is undefined.
  https://www.shellcheck.net/wiki/SC2048 -- Use "$@" (with quotes) to prevent...
  https://www.shellcheck.net/wiki/SC1091 -- Not following: /etc/default/vboot...