diff --git a/lib/font_renderer/agg_lcd_distribution_lut.h b/lib/font_renderer/agg_lcd_distribution_lut.h
index 2f794b5a..5e305d70 100644
--- a/lib/font_renderer/agg_lcd_distribution_lut.h
+++ b/lib/font_renderer/agg_lcd_distribution_lut.h
@@ -18,7 +18,7 @@
 #ifndef AGG_LCD_DISTRIBUTION_LUT_INCLUDED
 #define AGG_LCD_DISTRIBUTION_LUT_INCLUDED
 
-#include <cmath>
+#include <cstdlib>
 
 #include "agg_basics.h"