diff --git a/src/tools/smtp.h b/src/tools/smtp.h
index 9f7140537..426d5bc9d 100644
--- a/src/tools/smtp.h
+++ b/src/tools/smtp.h
@@ -27,6 +27,8 @@
 #include <vector>
 #include <cstdarg>
 #include <cstdio>
+#include <cstdlib>
+#include <cstring>
 #include <ctime>
 #include <cerrno>