diff --git a/tests/cefclient/browser/osr_renderer.cc b/tests/cefclient/browser/osr_renderer.cc
index e1344cdfc..f0e359756 100644
--- a/tests/cefclient/browser/osr_renderer.cc
+++ b/tests/cefclient/browser/osr_renderer.cc
@@ -9,6 +9,8 @@
 #define GL_GLEXT_PROTOTYPES
 #endif
 
+#include <math.h>
+
 #if defined(OS_WIN)
 #include <gl/gl.h>
 #elif defined(OS_MAC)