diff --git a/src/fu-common-cab.c b/src/fu-common-cab.c
index 7dee87959..c755b9b05 100644
--- a/src/fu-common-cab.c
+++ b/src/fu-common-cab.c
@@ -398,7 +398,7 @@ fu_common_cab_build_silo (GBytes *blob, guint64 size_max, GError **error)
 			     FWUPD_ERROR_INTERNAL,
 			     "failed to create temp dir: %s",
 			     error_local->message);
-		return FALSE;
+		return NULL;
 	}
 	helper.decompress_path = tmp_path;
 	tmp_file = g_file_new_for_path (tmp_path);
diff --git a/src/fu-common-guid.c b/src/fu-common-guid.c
index fe9006604..6adfeea96 100644
--- a/src/fu-common-guid.c
+++ b/src/fu-common-guid.c
@@ -46,9 +46,9 @@ fu_common_guid_from_data (const gchar *namespace_id,
 	uuid_t uu_new;
 	g_autoptr(GChecksum) csum = NULL;
 
-	g_return_val_if_fail (namespace_id != NULL, FALSE);
-	g_return_val_if_fail (data != NULL, FALSE);
-	g_return_val_if_fail (data_len != 0, FALSE);
+	g_return_val_if_fail (namespace_id != NULL, NULL);
+	g_return_val_if_fail (data != NULL, NULL);
+	g_return_val_if_fail (data_len != 0, NULL);
 
 	/* convert the namespace to binary */
 	rc = uuid_parse (namespace_id, uu_namespace);
@@ -58,7 +58,7 @@ fu_common_guid_from_data (const gchar *namespace_id,
 			     FWUPD_ERROR_NOT_SUPPORTED,
 			     "namespace '%s' is invalid",
 			     namespace_id);
-		return FALSE;
+		return NULL;
 	}
 
 	/* hash the namespace and then the string */