From a0206076648c166447dfa11444f6e331e5576705 Mon Sep 17 00:00:00 2001
From: Florian Renkin <frenkin@lrde.epita.fr>
Date: Mon, 6 Apr 2020 14:39:07 +0200
Subject: [PATCH] Correct an issue in toparity with parity prefix

* spot/twaalgos/toparity.cc: Use a lower value in the parity
prefix vector to avoid the creation of unwanted {0} marks.
---
 spot/twaalgos/toparity.cc | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/spot/twaalgos/toparity.cc b/spot/twaalgos/toparity.cc
index 7981684b1..37cf999f9 100644
--- a/spot/twaalgos/toparity.cc
+++ b/spot/twaalgos/toparity.cc
@@ -1443,7 +1443,8 @@ build_scc(twa_graph_ptr &sub_automaton,
           unsigned max_states = -1U)
 {
 
-    std::vector<int> parity_prefix_colors (SPOT_MAX_ACCSETS, -1);
+    std::vector<int> parity_prefix_colors (SPOT_MAX_ACCSETS,
+                                            - SPOT_MAX_ACCSETS - 2);
     unsigned min_prefix_color = SPOT_MAX_ACCSETS + 1;
     if (options.parity_prefix)
     {