diff --git a/configure.ac b/configure.ac
index 72da38d..5cb6a7c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -122,11 +122,6 @@ if test "x$XSERVER_LIBPCIACCESS" = xyes; then
 fi
 AM_CONDITIONAL(XSERVER_LIBPCIACCESS, test "x$XSERVER_LIBPCIACCESS" = xyes)
 
-# Checks for library functions
-# We don't use strlcat, strlcpy, or timingsafe_memcmp, but check to quiet
-# -Wredundant-decls warning from xorg/os.h which will otherwise redefine them.
-AC_CHECK_FUNCS([strlcat strlcpy timingsafe_memcmp])
-
 AC_SUBST([moduledir])
 
 DRIVER_NAME=sis