diff --git a/src/domain/conflicts/conflict_colinear_edges.cpp b/src/domain/conflicts/conflict_colinear_edges.cpp
index 55a50f5..64350a0 100644
--- a/src/domain/conflicts/conflict_colinear_edges.cpp
+++ b/src/domain/conflicts/conflict_colinear_edges.cpp
@@ -62,6 +62,7 @@ void ConflictColinearEdges::auto_solve(MeshlinePolicyManager& line_policy_manage
 				switch(axis.value()) {
 				case MeshlinePolicy::Axis::H: return Normal::YMIN;
 				case MeshlinePolicy::Axis::V: return Normal::XMIN;
+				default: abort();
 				}
 			} ();
 			meshline_policy = line_policy_manager.add_meshline_policy(
@@ -77,6 +78,7 @@ void ConflictColinearEdges::auto_solve(MeshlinePolicyManager& line_policy_manage
 				switch(axis.value()) {
 				case MeshlinePolicy::Axis::H: return Normal::YMAX;
 				case MeshlinePolicy::Axis::V: return Normal::XMAX;
+				default: abort();
 				}
 			} ();
 			meshline_policy = line_policy_manager.add_meshline_policy(
diff --git a/src/domain/geometrics/relation.cpp b/src/domain/geometrics/relation.cpp
index 420453a..b76d285 100644
--- a/src/domain/geometrics/relation.cpp
+++ b/src/domain/geometrics/relation.cpp
@@ -13,10 +13,10 @@ namespace relation {
 //******************************************************************************
 PolygonPoint cast(PolygonSegment const a) {
 	switch(a) {
-	default: [[fallthrough]];
 	case PolygonSegment::IN: return PolygonPoint::IN;
 	case PolygonSegment::ON: return PolygonPoint::ON;
 	case PolygonSegment::OUT: return PolygonPoint::OUT;
+	default: abort();
 	}
 }
 
diff --git a/src/domain/mesh/meshline_policy.cpp b/src/domain/mesh/meshline_policy.cpp
index 7e057c6..4c83104 100644
--- a/src/domain/mesh/meshline_policy.cpp
+++ b/src/domain/mesh/meshline_policy.cpp
@@ -48,5 +48,6 @@ Coord coord(Point const& point, MeshlinePolicy::Axis const axis) noexcept {
 	switch(axis) {
 	case MeshlinePolicy::Axis::H: return point.y;
 	case MeshlinePolicy::Axis::V: return point.x;
+	default: abort();
 	}
 }
diff --git a/src/domain/meshline_policy_manager.cpp b/src/domain/meshline_policy_manager.cpp
index 732c069..f44c8f7 100644
--- a/src/domain/meshline_policy_manager.cpp
+++ b/src/domain/meshline_policy_manager.cpp
@@ -105,5 +105,6 @@ GridAxis cast(MeshlinePolicy::Axis const a) noexcept {
 	switch(a) {
 	case MeshlinePolicy::Axis::H: return H;
 	case MeshlinePolicy::Axis::V: return V;
+	default: abort();
 	}
 }