From 0c710ce470ba143053228bc5a3aa107108207a20 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Uwe=20Kr=C3=BCger?=
 <45282134+UweKrueger@users.noreply.github.com>
Date: Fri, 9 Apr 2021 17:18:02 +0200
Subject: [PATCH] cgen: register `Option_void` when used for `chan <- x or
 {...}` (#9648)

---
 vlib/v/gen/c/cgen.v | 1 +
 1 file changed, 1 insertion(+)

diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 9019b30096..3459a762b0 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -670,6 +670,7 @@ static inline $opt_el_type __Option_${styp}_popval($styp ch) {
 fn (mut g Gen) register_chan_push_optional_call(el_type string, styp string) {
 	if styp !in g.chan_push_optionals {
 		g.chan_push_optionals << styp
+		g.register_optional(ast.void_type.set_flag(.optional))
 		g.channel_definitions.writeln('
 static inline Option_void __Option_${styp}_pushval($styp ch, $el_type e) {
 	if (sync__Channel_try_push_priv(ch, &e, false)) {