From f163e6a2ee1d28bd7d1110134e17071c9dc5c53c Mon Sep 17 00:00:00 2001
From: Filip Sykala <filip.sykala@prusa3d.cz>
Date: Tue, 4 Jan 2022 15:04:33 +0100
Subject: [PATCH] Fix type warning

---
 src/libslic3r/NSVGUtils.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/libslic3r/NSVGUtils.cpp b/src/libslic3r/NSVGUtils.cpp
index e86451e490..c5afaac6a6 100644
--- a/src/libslic3r/NSVGUtils.cpp
+++ b/src/libslic3r/NSVGUtils.cpp
@@ -49,7 +49,9 @@ ExPolygons NSVGUtils::to_ExPolygons(NSVGimage *image,
                  path           = path->next) {
                 // Flatten path
                 polygon.points.emplace_back(path->pts[0], path->pts[1]);
-                for (size_t i = 0; i < path->npts - 1; i += 3) {
+                size_t path_size = (path->npts > 1) ?
+                    static_cast<size_t>(path->npts - 1) : 0;
+                for (size_t i = 0; i < path_size; i += 3) {
                     float *p = &path->pts[i * 2];
                     Vec2f  p1(p[0], p[1]), p2(p[2], p[3]), p3(p[4], p[5]),
                         p4(p[6], p[7]);