In /usr/bin/autopkgtest-build-lxd line 41:
        RES=`apt-config shell proxy Acquire::http::Proxy`
            ^-- SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
        RES=$(apt-config shell proxy Acquire::http::Proxy)


In /usr/bin/autopkgtest-build-lxd line 42:
        eval $RES
             ^--^ SC2086: Double quote to prevent globbing and word splitting.

Did you mean: 
        eval "$RES"


In /usr/bin/autopkgtest-build-lxd line 43:
        if echo "${proxy:-}" | egrep -q '(localhost|127\.0\.0\.[0-9]*)'; then
                               ^---^ SC2196: egrep is non-standard and deprecated. Use grep -E instead.


In /usr/bin/autopkgtest-build-lxd line 46:
            local bridge_interface=$(lxc profile show default | sed -n '/parent:/ { s/^.*: *//; p; q }') || true
            ^--------------------^ SC2039: In POSIX sh, 'local' is undefined.
                  ^--------------^ SC2155: Declare and assign separately to avoid masking return values.


In /usr/bin/autopkgtest-build-lxd line 48:
                local bridge_ip=$(ip -4 a show dev "$bridge_interface" | awk '/ inet / {sub(/\/.*$/, "", $2); print $2}') || true
                ^-------------^ SC2039: In POSIX sh, 'local' is undefined.
                      ^-------^ SC2155: Declare and assign separately to avoid masking return values.


In /usr/bin/autopkgtest-build-lxd line 81:
        O=`lxc exec "$CONTAINER" runlevel 2>/dev/null </dev/null` || continue
          ^-- SC2006: Use $(...) notation instead of legacy backticked `...`.

Did you mean: 
        O=$(lxc exec "$CONTAINER" runlevel 2>/dev/null </dev/null) || continue


In /usr/bin/autopkgtest-build-lxd line 96:
    DISTRO=$(lxc exec "$CONTAINER" -- sh -ec 'lsb_release -si 2>/dev/null || . /etc/os-release; echo "${NAME% *}"' </dev/null)
                                             ^-- SC2016: Expressions don't expand in single quotes, use double quotes for that.


In /usr/bin/autopkgtest-build-lxd line 97:
    CRELEASE=$(lxc exec "$CONTAINER" -- sh -ec 'lsb_release -sc 2>/dev/null || awk "/^deb/ {sub(/\\[.*\\]/, \"\", \$0); print \$3; exit}" /etc/apt/sources.list' </dev/null)
                                               ^-- SC2016: Expressions don't expand in single quotes, use double quotes for that.


In /usr/bin/autopkgtest-build-lxd line 108:
    for script in $(dirname $(dirname "$0"))/setup-commands/setup-testbed \
                            ^-------------^ SC2046: Quote this to prevent word splitting.

For more information:
  https://www.shellcheck.net/wiki/SC2039 -- In POSIX sh, 'local' is undefined.
  https://www.shellcheck.net/wiki/SC2046 -- Quote this to prevent word splitt...
  https://www.shellcheck.net/wiki/SC2155 -- Declare and assign separately to ...