What are common reasons for receiving warning messages related to parameter types when using PHP functions?

Warning messages related to parameter types in PHP functions commonly occur when the function is expecting a specific data type for its parameters, but incorrect or mismatched data types are being passed in. To resolve this, make sure to pass the correct data types to the function as specified in its documentation or definition.

// Example of passing correct data types to a function
function addNumbers(int $num1, int $num2) {
    return $num1 + $num2;
}

// Correct usage
$result = addNumbers(5, 10);
echo $result; // Output: 15

// Incorrect usage (will trigger warning)
$result = addNumbers("5", 10); // Passing a string instead of an integer
echo $result; // Output: Warning: A non-numeric value encountered