diff --git a/src/math/lp/nla_core.cpp b/src/math/lp/nla_core.cpp
index 3d3c2efae..af1a79f92 100644
--- a/src/math/lp/nla_core.cpp
+++ b/src/math/lp/nla_core.cpp
@@ -102,7 +102,7 @@ bool core::canonize_sign(lpvar j) const {
 }
 
 bool core::canonize_sign_is_correct(const monic& m) const {
-    bool r = false;
+    bool r = m.sign();
     for (lpvar j : m.vars()) {
         r ^= canonize_sign(j);
     }