diff --git a/src/iri.c b/src/iri.c
index 7dcf3ac..1c8695c 100644
--- a/src/iri.c
+++ b/src/iri.c
@@ -189,9 +189,10 @@ do_conversion (const char *tocode, const char *fromcode, char const *in_org, siz
         {
           tooshort++;
           done = len;
-          len = outlen = done + inlen * 2;
-          s = xrealloc (s, outlen + 1);
-          *out = s + done;
+          len = done + inlen * 2;
+          s = xrealloc (s, len + 1);
+          *out = s + done - outlen;
+          outlen += inlen * 2;
         }
       else /* Weird, we got an unspecified error */
         {