fix

Author: felipensp

vlib/v/gen/c/assign.v

@@ -163,7 +163,7 @@ fn (mut g Gen) expr_with_opt(expr ast.Expr, expr_typ ast.Type, ret_typ ast.Type)
 		}
 		g.expr(expr)
 		if expr is ast.ComptimeSelector {
-			return '${expr.left.str()}.${g.comptime.comptime_for_field_value.name}'
+			return g.comptime_selector_str(expr)
 		} else {
 			return expr.str()
 		}

vlib/v/gen/c/cgen.v

@@ -3728,7 +3728,7 @@ fn (mut g Gen) expr(node_ ast.Expr) {
 				mut is_unwrapped := true
 				if mut node.expr is ast.ComptimeSelector && node.expr.left is ast.Ident {
 					// val.$(field.name)?
-					expr_str = '${node.expr.left.str()}.${g.comptime.comptime_for_field_value.name}'
+					expr_str = g.comptime_selector_str(node.expr)
 				} else if mut node.expr is ast.Ident && node.expr.ct_expr {
 					// val?
 					expr_str = node.expr.name

vlib/v/gen/c/comptime.v

@@ -39,6 +39,11 @@ fn (mut g Gen) comptime_selector(node ast.ComptimeSelector) {
 	}
 }
 
+fn (mut g Gen) comptime_selector_str(expr ast.ComptimeSelector) string {
+	arrow_or_dot := if expr.left_type.is_ptr() { '->' } else { '.' }
+	return '${expr.left.str()}${arrow_or_dot}${g.comptime.comptime_for_field_value.name}'
+}
+
 fn (mut g Gen) comptime_call(mut node ast.ComptimeCall) {
 	if node.is_embed {
 		// $embed_file('/path/to/file')

vlib/v/tests/options/option_var_test.v

@@ -22,7 +22,7 @@ mut:
 
 struct Decoder {}
 
-fn (d &Decoder) decode[T](typ T) T {
+fn (d &Decoder) decode[T](mut typ T) T {
 	$for field in T.fields {
 		$if field.is_option {
 			if typ.$(field.name) != none {
@@ -36,7 +36,7 @@ fn (d &Decoder) decode[T](typ T) T {
 
 fn test_comptime() {
 	d := Decoder{}
-	result := d.decode(StructType{
+	result := d.decode(mut StructType{
 		a: 'foo'
 		b: 3
 	})