https://github.com/coin-or/Bonmin/commit/3c51a306137f6f6f37825770987585b407919ff8

--- a/src/Algorithms/QuadCuts/BonQuadRow.cpp	2020-01-29 03:51:36.000000000 -0700
+++ b/src/Algorithms/QuadCuts/BonQuadRow.cpp	2021-07-20 11:22:40.885361344 -0600
@@ -89,8 +89,8 @@ QuadRow::operator=(const OsiRowCut &cut)
     c_ = 0;
     a_ = cut.row();
     Q_ = TMat();
-    g_.empty();
-    a_grad_idx_.empty();
+    g_.clear();
+    a_grad_idx_.clear();
     Q_row_grad_idx_.clear();
     Q_col_grad_idx_.clear();
     //Q_hessian_idx.empty();