diff --git a/src/libslic3r/Color.hpp b/src/libslic3r/Color.hpp
index cd1e82d794..3f93dc9194 100644
--- a/src/libslic3r/Color.hpp
+++ b/src/libslic3r/Color.hpp
@@ -6,6 +6,8 @@
 #include <array>
 #include <algorithm>
 
+#include <cassert>
+
 namespace Slic3r {
 using RGB = std::array<float, 3>;
 using RGBA = std::array<float, 4>;