Function references arguments but no caller passes any

Problem

ShellCheck performs a whole-script analysis and notices when a function's body reads positional parameters (`$1`, `$2`, `"$@"`, etc.) but every call to that function in the file passes no arguments at all. In that case the parameters the function reads are not the ones you probably intended — they leak in from the caller's own context — making the parameter references dead or misleading code. This is the mirror image of SC2119: SC2119 flags the call site (calling without args), SC2120 flags the function definition (expecting args nobody supplies).

Bad

log_message() {
  echo "[LOG] $1"
}

log_message   # called with no args anywhere in the script

Good

log_message() {
  local msg="$1"
  echo "[LOG] $msg"
}

log_message "starting up"

Explanation

Fix this by either passing the expected arguments at every call site, or, if the function is genuinely meant to take no input, removing the positional-parameter references and using a fixed value or an explicitly named variable instead. Consistently calling functions with the arguments they read makes data flow visible to both readers and static analysis.

Related

SC2119

SC2034

SC2124

When It Matters

The function reads $1, but no caller anywhere in the file supplies it. That is either dead parameter handling left behind by a refactor, or a call site that lost its argument — and in the second case the function silently operates on an empty value. It is a useful signal in long scripts where a helper gained a parameter and one of its five call sites was missed.

Second Example

Exceptions

A function that is part of a library sourced by other scripts has callers ShellCheck cannot see. Add "# shellcheck disable=SC2120" above the definition with a comment saying the function is part of the public interface of the file.

Faq