Fixed compiler warnings

src/libslic3r/Arrange/Core/NFP/EdgeCache.cpp

@@ -94,7 +94,7 @@ void fill_distances(const Polygon &poly, std::vector<double> &distances)
 
     double dist = 0.;
     auto lrange = line_range(poly);
-    for (const Line &l : lrange) {
+    for (const Line l : lrange) {
         dist += l.length();
         distances.emplace_back(dist);
     }

src/libslic3r/Arrange/Core/NFP/NFP.cpp

@@ -132,7 +132,7 @@ Polygon ifp_convex_convex(const Polygon &fixed, const Polygon &movable)
     // the zero area polygon formed by the edge. The union of all these sub-nfps
     // will contain a hole that is the actual ifp.
     auto lrange = line_range(fixed);
-    for (const Line &l : lrange) { // Older mac compilers generate warnging if line_range is called in-place
+    for (const Line l : lrange) { // Older mac compilers generate warnging if line_range is called in-place
         Polygon fixed = {l.a, l.b};
         subnfps.emplace_back(nfp_convex_convex_legacy(fixed, movable));
     }

src/libslic3r/Color.cpp

@@ -29,7 +29,7 @@ static void RGBtoHSV(float r, float g, float b, float& h, float& s, float& v)
 			h = 60.0f * (std::fmod(((g - b) / delta), 6.0f));
 		else if (max_comp == g)
 			h = 60.0f * (((b - r) / delta) + 2.0f);
-		else if (max_comp == b)
+		else  // max_comp == b
 			h = 60.0f * (((r - g) / delta) + 4.0f);
 
 		s = (max_comp > 0.0f) ? delta / max_comp : 0.0f;

src/libslic3r/Support/TreeSupport.cpp

@@ -81,7 +81,7 @@ static inline void validate_range(const MultiPoint &mp)
     validate_range(mp.points);
 }
 
-static inline void validate_range(const Polygons &polygons) 
+[[maybe_unused]] static inline void validate_range(const Polygons &polygons) 
 {
     for (const Polygon &p : polygons)
         validate_range(p);

src/slic3r/GUI/TextLines.cpp

@@ -154,7 +154,7 @@ TextLines select_closest_contour(const std::vector<Polygons> &line_contours) {
         std::vector<Linef> linesf = to_linesf(expolygons);
         AABBTreeIndirect::Tree2d tree = AABBTreeLines::build_aabb_tree_over_indexed_lines(linesf);
 
-        size_t line_idx;
+        size_t line_idx = 0;
         Vec2d  hit_point;
         // double distance = 
         AABBTreeLines::squared_distance_to_indexed_lines(linesf, tree, zero, line_idx, hit_point);

tests/libslic3r/test_support_spots_generator.cpp

@@ -72,7 +72,7 @@ TEST_CASE("Moments calculation for rotated axis.", "[SupportSpotsGenerator]") {
     Integrals integrals{{polygon}};
 
     std::mt19937 generator{std::random_device{}()};
-    std::uniform_real_distribution<float> angle_distribution{0, 2*M_PI};
+    std::uniform_real_distribution<float> angle_distribution{0.f, float(2*M_PI)};
 
     // Meassured counterclockwise from (1, 0)
     const float angle = angle_distribution(generator);