--- src/sort.c
+++ src/sort.c
@@ -748,7 +748,7 @@
 	  else
 	    {
 	      j += mblength;
-	      mblength = wcrtomb (mbc, wc, &state_wc);
+	      mblength = wcrtomb (mbc, pwc, &state_wc);
 	      assert (mblength != (size_t) 0 && mblength != (size_t) -1);
 	    }