diff --git a/transaction.go b/transaction.go
index edf419e..ad01f96 100644
--- a/transaction.go
+++ b/transaction.go
@@ -5,6 +5,7 @@ package pam
 #cgo CFLAGS: -Wall -Wno-unused-variable -std=c99
 #cgo LDFLAGS: -ldl -lpam
 
+#define _GNU_SOURCE
 #include <dlfcn.h>
 #include <security/pam_appl.h>
 #include <stdlib.h>
@@ -18,6 +19,10 @@ package pam
 #define BINARY_PROMPT_IS_SUPPORTED 0
 #endif
 
+#ifndef RTLD_NEXT
+# define RTLD_NEXT      ((void *) -1l)
+#endif
+
 void init_pam_conv(struct pam_conv *conv, uintptr_t);
 
 typedef int (*pam_start_confdir_fn)(const char *service_name, const char *user, const struct pam_conv *pam_conversation, const char *confdir, pam_handle_t **pamh);