Edit report at http://bugs.php.net/bug.php?id=45712&edit=1
ID: 45712
Comment by: jwvdveer at gmail dot com
Reported by: for-bugs at hnw dot jp
Summary: $something == NaN returns true with 5.3, false with
5.2.*
Status: Closed
Type: Bug
Package: Variables related
Operating System: *
PHP Version: 5.2CVS, 5.3CVS, 6CVS (2008-08-05)
Assigned To: tony2001
Block user comment: N
New Comment:
Please, reopen this bug. It's not working in PHP 5.3.3 on Windows
platform (released at 2010-07-21).
The behaviour of a comparison to NAN is the same as noted here.
It's not just a `me too`, but this thread shouln't have been closed.
Previous Comments:
------------------------------------------------------------------------
[2008-08-07 08:36:33] [email protected]
This bug has been fixed in CVS.
Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
Thank you for the report, and for helping us make PHP better.
------------------------------------------------------------------------
[2008-08-07 07:37:04] [email protected]
I'm testing a patch for it.
------------------------------------------------------------------------
[2008-08-05 12:52:06] for-bugs at hnw dot jp
NaN is not exact number. So, NaN should not equals itself. Additionaly,
NaN == NaN is false in C. You can see behavior of C as follows.
$ cat nan.c
int main() {double d;d=(-1e300*1e300)/(1e300*1e300);if (d==d) return 1;
else return 2;}
$ gcc nan.c; ./a.out; echo $?
2
$
------------------------------------------------------------------------
[2008-08-05 12:33:17] [email protected]
That $nan == $nan should be true. (like it is with 5.3)
------------------------------------------------------------------------
[2008-08-05 02:39:58] for-bugs at hnw dot jp
Description:
------------
There is == operator's problem dealing with NaN(Not a Number) in PHP
5.3.0alpha1. This behavior is different with PHP 5.0.0-5.2.6, so this is
compatibility problem.
Reproduce code:
---------------
<?php
$nan = (-1e300*1e300)/(1e300*1e300); // float(NAN)
var_dump($nan=='');
var_dump($nan==0.5);
var_dump($nan==50);
var_dump($nan=='500');
var_dump($nan=='abc');
var_dump($nan==$nan);
Expected result:
----------------
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
bool(false)
Actual result:
--------------
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)
------------------------------------------------------------------------
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Edit this bug report at http://bugs.php.net/bug.php?id=45712&edit=1