[gnumeric] Solver: run update_derived in ::prepare.

[Morten Welinder <mortenw src gnome org>]

commit 24ec0b1aec8901322e50acb7ad5270b6e453b47c
Author: Morten Welinder <terra gnome org>
Date:   Mon Feb 15 13:33:11 2021 -0500

    Solver: run update_derived in ::prepare.

 src/tools/ChangeLog    | 5 +++++
 src/tools/gnm-solver.c | 2 ++
 2 files changed, 7 insertions(+)
---
diff --git a/src/tools/ChangeLog b/src/tools/ChangeLog
index 24eefd5b2..4980a527b 100644
--- a/src/tools/ChangeLog
+++ b/src/tools/ChangeLog
@@ -1,3 +1,8 @@
+2021-02-15  Morten Welinder  <terra gnome org>
+
+       * gnm-solver.c (gnm_solver_prepare): Always run update_derived
+       here as someone could have changed the parameters underneath us.
+
 2020-08-12  Morten Welinder <terra gnome org>
 
        * Release 1.12.48
diff --git a/src/tools/gnm-solver.c b/src/tools/gnm-solver.c
index 9bcab0f96..9358fb306 100644
--- a/src/tools/gnm-solver.c
+++ b/src/tools/gnm-solver.c
@@ -1063,6 +1063,8 @@ gnm_solver_prepare (GnmSolver *sol, WorkbookControl *wbc, GError **err)
        g_return_val_if_fail (GNM_IS_SOLVER (sol), FALSE);
        g_return_val_if_fail (sol->status == GNM_SOLVER_STATUS_READY, FALSE);
 
+       gnm_solver_update_derived (sol);
+
        g_signal_emit (sol, solver_signals[SOL_SIG_PREPARE], 0, wbc, err, &res);
        return res;
 }