`M6-5-5`: Consider `const` when determining whether an escaped reference modifies

[lcartey]

Affected rules

• M6-5-5

Description

M6-5-5 identifies cases where a loop control variable is modified in the condition of a loop. It identifies two kinds of modifications: direct modification, and indirect modification - where a reference to the loop counter variable escapes the local scope, and could be modified. We currently assume that any reference that escapes the scope could be modified, but we should factor in whether the escaping function is const/non-const.

Specifically, we need to use isAddressOfAccessNonConst() instead of isAddressOfAccess() here:

codeql-coding-standards/cpp/common/src/codingstandards/cpp/Loops.qll

Line 263 in 47c8a57

loopControlVariableAccess.isAddressOfAccess()

Example

void loop(std::vector v) {
  std::vector<int>::iterator first = v.begin();
  std::vector<int>::iterator last = v.end();
  for (; first != last; first++) { // call to operator!= passes a reference to first
  }
}