Silent Type Cast

<?php

//declare(strict_types=1);

function foo(float $x): int {
    var_dump($x);
    
    return $x;
}

var_dump(foo(1));
//var_dump(foo(1.1));

An integer is a float, but the opposite is not always true. For PHP, pushing an integer in a function that types float its argument, makes that integer an float. The reverse conversion from float to integer is also possible, at return time. This happens when strict_types is not activated, and when the float has no decimal part, as is the case here.

Otherwise, it is a Type error, or an warning about loss of precision.

See Also

• Integers to floats, and back [Try me]

PHP Error Messages

• Return value must be of type int, float returned
• Implicit conversion from float 1.1 to int loses precision

PHP Features

• cast
• type-juggling
• implicit
• null
• integer
• silent

Last updated: 10 September 2026