void called() {}
void caller() {
  called();
}

/*
OUTPUT:
{
  "includes": [],
  "skipped_by_preprocessor": [],
  "usr2func": [{
      "usr": 468307235068920063,
      "detailed_name": "void called()",
      "qual_name_offset": 5,
      "short_name": "called",
      "kind": 12,
      "storage": 1,
      "declarations": [],
      "spell": "1:6-1:12|0|1|2",
      "extent": "1:1-1:17|0|1|0",
      "declaring_type": 0,
      "bases": [],
      "derived": [],
      "vars": [],
      "uses": ["3:3-3:9|11404881820527069090|3|32"],
      "callees": []
    }, {
      "usr": 11404881820527069090,
      "detailed_name": "void caller()",
      "qual_name_offset": 5,
      "short_name": "caller",
      "kind": 12,
      "storage": 1,
      "declarations": [],
      "spell": "2:6-2:12|0|1|2",
      "extent": "2:1-4:2|0|1|0",
      "declaring_type": 0,
      "bases": [],
      "derived": [],
      "vars": [],
      "uses": [],
      "callees": ["3:3-3:9|468307235068920063|3|32"]
    }],
  "usr2type": [],
  "usr2var": []
}
*/