`#[NoDiscard]` and `(void)` - some errors cannot be ignored

[DanielEScherzer]

Description

The following code:

<?php

$count = 0;

#[NoDiscard]
function incCount() {
	global $count;
	$count++;
	return $count;
}

for ( $count = 0; $count < 3; incCount() ) {
	echo $count . "\n";
}

Resulted in this output:

0

Warning: The return value of function incCount() should either be used or intentionally ignored by casting it as (void) in /in/rnVPV on line 12
1

Warning: The return value of function incCount() should either be used or intentionally ignored by casting it as (void) in /in/rnVPV on line 12
2

Warning: The return value of function incCount() should either be used or intentionally ignored by casting it as (void) in /in/rnVPV on line 12

But when I added void:

Parse error: syntax error, unexpected token "(void)", expecting ")" in /in/TQrqs on line 12

Process exited with code 255.

PHP Version

PHP master

Operating System

No response