ignoredErrors causing memory exhaustion

[nbalena28]

This is:

- [x] a bug report?
- [ ] a feature request
- [ ] **not** a usage question (ask them on https://stackoverflow.com/questions/tagged/phpspreadsheet or https://gitter.im/PHPOffice/PhpSpreadsheet)

What is the current behavior?
It is throwing an Allowed memory size of bytes exhausted exception

What are the steps to reproduce?
Here is an Excel file to reproduce this behavior with sample.xlsx

$reader = IOFactory::createReader('Xlsx');
$spreadsheet = $reader->load('sample.xlsx');

What features do you think are causing the issue

PhpSpreadsheet/src/PhpSpreadsheet/Reader/Xlsx.php

Lines 2381 to 2385 in 82ac7ab

	$sqref = (string) ($attributes['sqref'] ?? '');
	$numberStoredAsText = (string) ($attributes['numberStoredAsText'] ?? '');
	$formula = (string) ($attributes['formula'] ?? '');
	$twoDigitTextYear = (string) ($attributes['twoDigitTextYear'] ?? '');
	$evalError = (string) ($attributes['evalError'] ?? '');

The processIgnoredErrors is iterating IT (254) upto 62680 rows

Does an issue affect all spreadsheet file formats? If not, which formats are affected?
At least xlsx

Which versions of PhpSpreadsheet and PHP are affected?
PhpSpreadsheet 1.29.6 upto 4.0
PHP 7.4 | 8.3

[oleibman]

Not that it matters, but where is this bogus data coming from? Not one of the gazillion cells identified in the "ignore errors" range even exists.

I think ignored errors should not be processed if you specify readDataOnly. I will make that change. That should fix the memory problem for your sheet, and also greatly reduce the run time.

If readDataOnly is not an option, I also think ignored errors should not be processed for cells that don't exist. I will make that change. That should fix the memory problem for your sheet. It will, unfortunately, not have much effect on run time - we will still need to check the existence of each of the cells.