FALSE POSITIVE: `zerodiv` reports inside an unreachable branch after a noreturn call

[Rodri]

Hi, I found a false positive in Cppcheck 2.21.0 when a helper either calls a noreturn function or returns zero.

Affected tool

Cppcheck 2.21.0

Affected checker

Cppcheck zerodiv

Minimal reproducer

void stop(void) __attribute__((noreturn));

int zero_or_stop(int condition) {
  if (condition)
    stop();
  return 0;
}

int unreachable_division(int condition) {
  int zero = 0;
  if (zero_or_stop(condition))
    return 1 / zero;
  return 0;
}

Reproduction command

cppcheck --version
cppcheck --enable=warning --std=c11 --checkers-report=checkers.txt --template='{file}:{line}:{column}: [{id}] {message}' cppcheck-zerodiv-fp-noreturn-summary.c

Current behavior

Cppcheck reports cppcheck-zerodiv-fp-noreturn-summary.c:12:14: [zerodiv] Division by zero.

Expected behavior

Cppcheck should not report zerodiv. zero_or_stop either does not return or returns zero, so the branch containing the division is unreachable.

[CHR]

Looks like an instance of https://trac.cppcheck.net/ticket/14969
There already is a condition attached to the error message.