-int extra = (pcount != NULL)? *pcount : 0;
-uschar **argv =
- store_get((extra + acount + MAX_CLMACROS + 16) * sizeof(char *));
+int extra = pcount ? *pcount : 0;
+uschar **argv;
+
+#if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS)
+if (tls_requiretls) extra++;
+#endif
+
+argv = store_get((extra + acount + MAX_CLMACROS + 18) * sizeof(char *));