diff --git a/src/raster/undo.h b/src/raster/undo.h
index d8b879283..d52e141d7 100644
--- a/src/raster/undo.h
+++ b/src/raster/undo.h
@@ -19,7 +19,6 @@
 #ifndef RASTER_UNDO_H_INCLUDED
 #define RASTER_UNDO_H_INCLUDED
 
-#include <string.h>		/* for strlen */
 #include <vector>
 
 #include "raster/gfxobj.h"