diff --git a/raytracer.hpp b/raytracer.hpp
index 3008e44..93aa5d1 100644
--- a/raytracer.hpp
+++ b/raytracer.hpp
@@ -40,7 +40,7 @@ namespace cmath {
 
 // libstdc++ provides some constexpr math functions as an extension, so
 // use them if we can.
-#ifdef __GLIBCXX__
+#if defined(__GLIBCXX__) && !defined(__clang__)
 #define HAVE_CONSTEXPR_STD_MATH
 #endif