Index: configure.ac
--- configure.ac.orig
+++ configure.ac
@@ -427,7 +427,7 @@ AC_FUNC_STAT
 AC_FUNC_VPRINTF
 AC_CHECK_FUNCS([ \
 	getpass gettimeofday getline memset mkdir \
-	strdup strerror memset_s explicit_bzero \
+	strdup strerror memset_s explicit_bzero calloc_conceal \
 	strnlen sigaction
 ])