Fixed a divide by zero error in IFCBoolean that was latent, but nevertheless a bug

code/IFCBoolean.cpp

@@ -272,7 +272,6 @@ bool IntersectsBoundaryProfile(const IfcVector3& e0, const IfcVector3& e1, const
         const IfcVector3& b0 = boundary[i];
         const IfcVector3& b1 = boundary[(i + 1) % bcount];
         IfcVector3 b = b1 - b0;
-        IfcFloat b_sqlen_inv = 1.0 / b.SquareLength();
 
         // segment-segment intersection
         // solve b0 + b*s = e0 + e*t for (s,t)
@@ -281,6 +280,7 @@ bool IntersectsBoundaryProfile(const IfcVector3& e0, const IfcVector3& e1, const
             // no solutions (parallel lines)
             continue;
         }
+        IfcFloat b_sqlen_inv = 1.0 / b.SquareLength();
 
         const IfcFloat x = b0.x - e0.x;
         const IfcFloat y = b0.y - e0.y;