diff --git a/lib/config/config.c b/lib/config/config.c
index 51b869beb..ba16d291a 100644
--- a/lib/config/config.c
+++ b/lib/config/config.c
@@ -72,7 +72,7 @@ static int _tok_match(const char *str, const char *b, const char *e);
 /*
  * public interface
  */
-struct config_file *create_config_file()
+struct config_file *create_config_file(void)
 {
         struct cs *c;
         struct pool *mem = pool_create(10 * 1024);
diff --git a/lib/config/config.h b/lib/config/config.h
index 6a2159a2c..81bb4ab5f 100644
--- a/lib/config/config.h
+++ b/lib/config/config.h
@@ -34,7 +34,7 @@ struct config_file {
         struct config_node *root;
 };
 
-struct config_file *create_config_file();
+struct config_file *create_config_file(void);
 void destroy_config_file(struct config_file *cf);
 
 int read_config(struct config_file *cf, const char *file);
diff --git a/lib/format1/format1.c b/lib/format1/format1.c
index 036665ad6..18c0009f8 100644
--- a/lib/format1/format1.c
+++ b/lib/format1/format1.c
@@ -451,6 +451,11 @@ struct io_space *create_lvm1_format(const char *prefix, struct pool *mem,
 {
 	struct io_space *ios = dbg_malloc(sizeof(*ios));
 
+	if (!ios) {
+		stack;
+		return NULL;
+	}
+
 	ios->get_vgs = _get_vgs;
 	ios->get_pvs = _get_pvs;
 	ios->pv_read = _pv_read;
diff --git a/lib/format1/format1.h b/lib/format1/format1.h
index cac9f68ea..d20b6b123 100644
--- a/lib/format1/format1.h
+++ b/lib/format1/format1.h
@@ -4,8 +4,8 @@
  * This file is released under the GPL.
  */
 
-#ifndef LVM_FORMAT1_H
-#define LVM_FORMAT1_H
+#ifndef _LVM_FORMAT1_H
+#define _LVM_FORMAT1_H
 
 #include "metadata.h"