diff --git a/freeglut/freeglut/CMakeLists.txt b/freeglut/freeglut/CMakeLists.txt
index bf77354..b151e4f 100644
--- a/freeglut/freeglut/CMakeLists.txt
+++ b/freeglut/freeglut/CMakeLists.txt
@@ -123,6 +123,8 @@ CHECK_INCLUDE_FILES(fcntl.h 	HAVE_FCNTL_H)
 CHECK_INCLUDE_FILES(errno.h 	HAVE_ERRNO_H)
 CHECK_INCLUDE_FILES(usbhid.h 	HAVE_USBHID_H)
 CHECK_FUNCTION_EXISTS(gettimeofday HAVE_GETTIMEOFDAY)
+CHECK_FUNCTION_EXISTS(vfprintf HAVE_VFPRINTF)
+CHECK_FUNCTION_EXISTS(_doprnt HAVE_DOPRNT)
 
 # The generated config.h is placed in the project's build directory, just to
 # ensure that all CMake-generated files are kept away from the main source tree.
diff --git a/freeglut/freeglut/config.h.in b/freeglut/freeglut/config.h.in
index fe14591..c1467bc 100644
--- a/freeglut/freeglut/config.h.in
+++ b/freeglut/freeglut/config.h.in
@@ -9,4 +9,6 @@
 #cmakedefine HAVE_FCNTL_H
 #cmakedefine HAVE_ERRNO_H
 #cmakedefine HAVE_USBHID_H
-#cmakedefine HAVE_GETTIMEOFDAY
\ No newline at end of file
+#cmakedefine HAVE_GETTIMEOFDAY
+#cmakedefine HAVE_VFPRINTF
+#cmakedefine HAVE_DOPRNT