diff --git a/src/common.c b/src/common.c
index b923bb3..536b044 100644
--- a/src/common.c
+++ b/src/common.c
@@ -439,6 +439,7 @@
     if (*dest) {
         *dest = ly_realloc(*dest, len);
         if (!*dest) {
+            va_end(fp);
             return LY_EMEM;
         }
         *dest = strcat(*dest, addition);