casting doubles to ints
| From: | Iain Lewis | Date: | Wed, 04 Feb 2009 16:28:16 +0000 |
| Subject: | casting doubles to ints | ||
| Groups: | php.internals | ||
| Request: | Send a blank email to internals+get-42918@lists.php.net to get a copy of this message | ||
Hello all,
I wanted to suggest back porting the behaviour of the DVAL_TO_LVAL macro from zend_operators.h from 5.3 to 5.2, and wondered whether people thought this was a good idea or not?
The reason I want to do this is that while writing some tests, I noticed that the behaviour of casting a float to an int is a bit counter-intuitive on 64bit platforms for PHP 5.2. It looks as though this has been fixed in 5.3, and it would seem like a good idea to put this change back to 5.2 as well. From a personal point of view, it would mean I could write one test that would work on both 5.2 and 5.3, but it also seems like a sensible change, as the current behaviour is non-obvious. The change would cause some current tests to break, but I am happy to do the work to fix those up.
This is how a few expressions get evaluated at the moment. Changing the macro would make the 5.2 behaviour match 5.3
Expression 5.3 (RHEL5-64) 5.2 (RHEL5-64)(int) (PHP_INT_MAX) 9223372036854775807 9223372036854775807 (int) (PHP_INT_MAX + 1) 9223372036854775807 -9223372036854775808 (int) (PHP_INT_MAX + 1000) 9223372036854775807 -9223372036854775808 (int) (PHP_INT_MAX + 10000) 9223372036854775807 -9223372036854765568 Does this seem like a good change?