diff --git a/src/decode_aprs.c b/src/decode_aprs.c
index d00d8ffe..561d834a 100644
--- a/src/decode_aprs.c
+++ b/src/decode_aprs.c
@@ -3935,10 +3935,11 @@ static void decode_tocall (decode_aprs_t *A, char *dest)
  * models before getting to the more generic APY.
  */
 
-#if defined(__WIN32__) || defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__APPLE__)
-	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), tocall_cmp);
-#else
+#if defined(__linux__)
+	    /* glibc defines __compar_fn_t, which is not defined by POSIX. */
 	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), (__compar_fn_t)tocall_cmp);
+#else
+	    qsort (tocalls, num_tocalls, sizeof(struct tocalls_s), tocall_cmp);
 #endif
 	  }
 	  else {