diff --git a/libs/kimath/src/geometry/shape_poly_set.cpp b/libs/kimath/src/geometry/shape_poly_set.cpp
index 3ef6b90333..b221264fde 100644
--- a/libs/kimath/src/geometry/shape_poly_set.cpp
+++ b/libs/kimath/src/geometry/shape_poly_set.cpp
@@ -1207,7 +1207,7 @@ void SHAPE_POLY_SET::unfractureSingle( SHAPE_POLY_SET::POLYGON& aPoly )
     int outline = -1;
 
     POLYGON result;
-    double max_poly;
+    double max_poly = 0.0;
 
     while( queue.size() )
     {