diff --git a/src/evalfunc.c b/src/evalfunc.c
index afc8977..b387c8c 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -1982,7 +1982,7 @@
     if (argvars[1].v_type != VAR_UNKNOWN)
 	noref = (int)tv_get_bool_chk(&argvars[1], NULL);
     if (noref < 0 || noref > 1)
-	emsg(_(e_invarg));
+	semsg(_(e_using_number_as_bool_nr), noref);
     else
     {
 	copyID = get_copyID();
@@ -8193,7 +8193,7 @@
     if (argvars[1].v_type != VAR_UNKNOWN)
 	skipcc = (int)tv_get_bool(&argvars[1]);
     if (skipcc < 0 || skipcc > 1)
-	emsg(_(e_invarg));
+	semsg(_(e_using_number_as_bool_nr), skipcc);
     else
     {
 	func_mb_ptr2char_adv = skipcc ? mb_ptr2char_adv : mb_cptr2char_adv;