diff --git a/src/input_init.c b/src/input_init.c
index 1438c3e52..11f020dad 100644
--- a/src/input_init.c
+++ b/src/input_init.c
@@ -24,6 +24,7 @@
 #include "conf.h"
 #include "glib_compat.h"
 
+#include <assert.h>
 #include <string.h>
 
 static inline GQuark
@@ -67,6 +68,11 @@ input_stream_global_init(GError **error_r)
 
 	for (unsigned i = 0; input_plugins[i] != NULL; ++i) {
 		const struct input_plugin *plugin = input_plugins[i];
+
+		assert(plugin->name != NULL);
+		assert(*plugin->name != 0);
+		assert(plugin->open != NULL);
+
 		const struct config_param *param =
 			input_plugin_config(plugin->name, &error);
 		if (param == NULL && error != NULL) {