With regards to the original post, your use of $GLOBALS was incorrect. The correction would be unset($GLOBALS['myArray'][$i]);

The reason is found in the code, not the PHP engine. Passing the array by reference or value is not really the key point; the problem was accessing the correct structure in the $GLOBALS array.

However, it would probably be more beneficial to start over and work with a reference to the array within the function as it would alleviate the need to have the global variable always named $myArray.

The warnings about call-time pass-by-reference being deprecated are only raised when you try to pass an argument as a reference when calling a function (e.g. $blah = myfunc(&$array)) and not when defining a function as accepting arguments by reference (e.g. function myfunc(&$array)).