Gentoo bug #458790
--- a/include/sasl.h
+++ b/include/sasl.h
@@ -121,6 +121,9 @@
 #ifndef SASL_H
 #define SASL_H 1
 
+/* stddef.h to get size_t defined */
+#include <stddef.h>
+
 /* Keep in sync with win32/common.mak */
 #define SASL_VERSION_MAJOR 2
 #define SASL_VERSION_MINOR 1
