diff --git a/boost/boost/test/impl/debug.ipp b/boost/boost/test/impl/debug.ipp
index bee956c1cb..0e816fbd02 100644
--- a/boost/boost/test/impl/debug.ipp
+++ b/boost/boost/test/impl/debug.ipp
@@ -68,7 +68,7 @@ namespace std { using ::memset; using ::sprintf; }
 #  include <sys/stat.h>
 #  include <sys/wait.h>
 #  include <sys/time.h>
-#  include <stdio.h>
+#  include <cstdio>
 #  include <stdlib.h>
 
 #  if defined(sun) || defined(__sun)