Warning: `parse_str()` can cause "Input variables exceeded 1000" error (1000 is default php.ini setting for `max_input_vars`).

Test code.

<?php

$inputString = 'first=firstvalue';

for ($i = 1; $i <= 1100; $i++) {
    $inputString .= '&arrLoopNumber[]=' . $i;
}
unset($i);

echo 'input string: <code>' . $inputString . '</code><br>' . PHP_EOL;
echo '<h5>doing <code>parse_str()</code></h5>' . PHP_EOL;

$output = [];
parse_str($inputString, $output);
// errors!!
?>