Bug #81601 [Csd->Nab]: float - (int) float is sometimes bigger than 1

Edit report at https://bugs.php.net/bug.php?id=81601&edit=1 ID: 81601 Updated by: requinix@php.net Reported by: dktapps at pmmp dot io Summary: float - (int) float is sometimes bigger than 1 -Status: Closed +Status: Not a bug Type: Bug Package: Math related Operating System: Linux PHP Version: 8.0.13 Block user comment: N Private report: N New Comment: > HOWEVER, the fact that debug backtraces contain the current values of parameter > variables, rather than the values actually passed, is a very unexpected and > confusing behaviour which really ought to be fixed. See: https://www.php.net/manual/en/migration70.incompatible.php#migration70.incompatible.other.func-parameter-modified https://bugs.php.net/bug.php?id=79827 Previous Comments: ------------------------------------------------------------------------ [2021-12-10 17:20:43] dktapps at pmmp dot io Hi all, the mystery has been solved. The cause of the confusion was this code: https://github.com/pmmp/PocketMine-MP/blob/eb9012401b6510fc24df44d9ff5545c8094f7471/src/entity/ExperienceManager.php#L201 The variable $progress is the name of a parameter, but its value is being overridden by some value from PlayerExperienceChangeEvent, which does not check bounds. TL;DR: This was caused by some third party code. HOWEVER, the fact that debug backtraces contain the current values of parameter variables, rather than the values actually passed, is a very unexpected and confusing behaviour which really ought to be fixed. ------------------------------------------------------------------------ [2021-12-03 13:01:21] dktapps at pmmp dot io I'll also mention that NO references are used in the stack, so I don't know how this is happening. ------------------------------------------------------------------------ [2021-12-03 12:58:47] dktapps at pmmp dot io Hi all, this issue recently occurred again despite additional checks in the code specifically designed to trap this edge case. It looks like the value must be getting corrupted somewhere. Unsuccessful trap: https://github.com/pmmp/PocketMine-MP/blob/6b7d0307afb36a7faca2dd65734e15000baf17ba/src/pocketmine/entity/Human.php#L401 Error thrown here: https://github.com/pmmp/PocketMine-MP/blob/6b7d0307afb36a7faca2dd65734e15000baf17ba/src/pocketmine/entity/Attribute.php#L196 https://crash.pmmp.io/view/5558770 ------------------------------------------------------------------------ [2021-11-10 13:28:24] antonino dot spampinato86 at gmail dot com Yes, the integer part of the float storage of the implicit integer cast is equivalent to the integer part of the float. But from the source you mentioned I see two numbers with different lengths and I suspect there is a problem with the scientific notation for 0. If you can also print with var_dump(sprintf('%00.53F', $float)); when in source it checks if > 0 so you will have two representations of the number that you can compare for debugging. ------------------------------------------------------------------------ [2021-11-10 09:39:26] php at leinertco dot com Try to pass $newLevel as 3rd argument in setXpAndProgress, so you have its value in your logs. Maybe this will help :/ ------------------------------------------------------------------------ The remainder of the comments for this report are too long. To view the rest of the comments, please view the bug report online at https://bugs.php.net/bug.php?id=81601 -- Edit this bug report at https://bugs.php.net/bug.php?id=81601&edit=1