Gap analysis — c13 in decision #845

scry-mcdc · malloc.c:4897 · branch 5952

Status: GAP

What you need

To prove condition c13 independently affects the decision, you need a row where c13 = T and the outcome differs from row 2448 (where c13 = F).

Required condition vector:

  c0 = *
  c1 = *
  c2 = *
  c3 = *
  c4 = *
  c5 = *
  c6 = *
  c7 = *
  c8 = *
  c9 = *
  c10 = *
  c11 = *
  c12 = F
  c13 = T
  c14 = T
  c15 = *
  c16 = *
  c17 = *

Conditions marked * were short-circuited in the baseline row; the new test must drive inputs so they get evaluated to either T or F.

Suggested test stub

#[test]
fn closes_gap_d845_c13() {
    // Verdict: scry-mcdc
    // Source: malloc.c:4897
    // Branch:  5952
    //
    // TODO: drive the function so condition c13 evaluates to the
    // value above and the resulting decision outcome differs from
    // the existing pair row.
    todo!("witness viz: gap drill-down for d#845/c13");
}

After adding the test, re-run: witness instrument && witness run --invoke run_row_NEW && witness report. The condition should flip from gap to proved.