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to handle this bug. Please re-read the instructions at
http://bugs.php.net/how-to-report.php

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to this bug and change the status back to "Open".

Thank you for your interest in PHP.

Oops, I meant


Thank you for this bug report. To properly diagnose the problem, we
need a short but complete example script to be able to reproduce
this bug ourselves. 

A proper reproducing script starts with ,
is max. 10-20 lines long and does not require any external 
resources such as databases, etc. If the script requires a 
database to demonstrate the issue, please make sure it creates 
all necessary tables, stored procedures etc.

Please avoid embedding huge scripts into the report.

Test script:
---------------
<?php
$im = imagecreatefrombmp('./php.bmp');

// Save the image
var_dump(imagebmp($im, './php.bmp'));

// Free up memory
imagedestroy($im);


Expected result:
----------------
PHP Warning:  imagecreatefrombmp(): './php.bmp' is not a valid BMP file in /root/bmp.php on line 3
PHP Warning:  imagebmp() expects parameter 1 to be resource, bool given in /root/bmp.php on line 6
bool(false)
PHP Warning:  imagedestroy() expects parameter 1 to be resource, bool given in /root/bmp.php on line 9

Actual result:
--------------
An error as follows:

PHP Warning:  imagecreatefrombmp(): './php.bmp' is not a valid BMP file in /root/bmp.php on line 3
PHP Warning:  imagebmp() expects parameter 1 to be resource, bool given in /root/bmp.php on line 6
NULL
PHP Warning:  imagedestroy() expects parameter 1 to be resource, bool given in /root/bmp.php on line 9

https://www.php.net/manual/en/functions.internal.php
> Note: If the parameters given to a function are not what it expects, such as passing an array where a string is
> expected, the return value of the function is undefined. In this case it will likely return NULL but this is just
> a convention, and cannot be relied upon.

imagecreatefrombmp() failed. imagebmp() is returning NULL because the $im argument is invalid.