Bug #53934 [Com]: The negative PHP_INT_MAX is incorrectly converted to float

Edit report at https://bugs.php.net/bug.php?id=53934&edit=1

 ID:                 53934
 Comment by:         ajf at ajf dot me
 Reported by:        eriksen dot costa at infranology dot com dot br
 Summary:            The negative PHP_INT_MAX is incorrectly converted to
                     float
 Status:             Verified
 Type:               Bug
 Package:            Scripting Engine problem
 Operating System:   Linux
 PHP Version:        5.3.5
 Block user comment: N
 Private report:     N

 New Comment:

Since PHP 7 there is PHP_INT_MIN for this purpose, by the way.


Previous Comments:
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[2014-06-05 15:12:15] ajf at ajf dot me

OK, I found out why this happens. Because the difference between subtraction and negation can't be known at lexing time ($x = 12-3 vs $x = -3), -9223372036854775808 is actually parsed as -(9223372036854775808). Since signed integers are asymettrical (max is 9223372036854775807 but min is -9223372036854775808), 9223372036854775808 overflows and becomes a float. Then the parser sees -(9.2233720368548E+18) and subtracts it, yielding -9.2233720368548E+18.

I'm not sure how this could be fixed short of parsing numbers at the last minute. Maybe that would actually reap performance benefits!

------------------------------------------------------------------------
[2014-06-05 14:37:19] ajf at ajf dot me

This issue still exists in master.

------------------------------------------------------------------------
[2012-08-09 14:05:43] ajf at ajf dot me

@catphract:

In that case is it not a tokeniser issue, and "-9223372036854775807" should be 
tokenised to '-9223372036854775807' not '-' '9223372036854775807'?

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[2011-02-05 18:55:33] [email protected]

The problem is that "-9223372036854775808" is not parsed as an integer, instead the minus sign and the rest are parsed individually and 9223372036854775808 is bigger than LONG_MAX.

Probably this is not trivial to fix.

------------------------------------------------------------------------
[2011-02-05 14:53:32] eriksen dot costa at infranology dot com dot br

Description:
------------
I found this and seems a bug. Everytime I use the negative PHP_INT_MAX literally (-9223372036854775808) as a function parameter, it is converted to float.

However, if I pass it like an expression -9223372036854775807 - 1, it is correctly identified as an integer.

Test script:
---------------
--TEST--
Checks if the negative PHP_INT_MAX is treated as integer.
--CREDITS--
Eriksen Costa <[email protected]>
--SKIPIF--
<?php
if (PHP_INT_SIZE < 8) die('64bit platforms only');
?>
--FILE--
<?php
var_dump(-9223372036854775807 - 1);
var_dump((PHP_INT_MAX * -1) - 1);
var_dump(-9223372036854775808);
?>
--EXPECT--
int(-9223372036854775808);
int(-9223372036854775808);
int(-9223372036854775808);

Expected result:
----------------
int(-9223372036854775808);
int(-9223372036854775808);
int(-9223372036854775808);

Actual result:
--------------
int(-9223372036854775808)
int(-9223372036854775808)
float(-9.2233720368548E+18)



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Edit this bug report at https://bugs.php.net/bug.php?id=53934&edit=1