Critical Fatal Error – Infinite Recursion in WPML (Confirmed Not Server-Side Issue)

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Tagged: Bug

This topic contains 4 replies, has 0 voices.

Last updated by Itamar 2 weeks ago.

Assisted by: Itamar.

Author	Posts
February 3, 2026 at 5:44 pm
dianaV-9	Hello WPML Support Team, I would like to follow up on a critical fatal error related to WPML, with additional confirmation from our hosting provider. Error message: Critical Uncaught Error: Maximum call stack size of 8339456 bytes (zend.max_allowed_stack_size - zend.reserved_stack_size) reached. Infinite recursion? File: /wp-content/plugins/sitepress-multilingual-cms/vendor/wpml/fp/core/Fns.php Line: 202 This error occurs repeatedly and causes site instability. Hosting provider investigation (important) We have asked our hosting provider to fully investigate this issue on the server level. After reviewing server-side logs, PHP configuration, and recent system changes, they confirmed the following: This is not a server-side or PHP configuration issue No recent server or PHP updates were made that could cause this behavior PHP version and stack/memory-related settings are correctly configured Modifying zend.max_allowed_stack_size would not be a real solution, as the root cause is an application-level infinite recursion The error clearly points to a logical issue inside the WPML plugin, or a compatibility conflict between WPML and another plugin or the active theme According to the hosting provider, the error indicates that a WPML internal function repeatedly calls itself in an infinite loop, which PHP interrupts for safety reasons. Environment details WordPress: latest stable WPML Multilingual CMS: latest version WPML add-ons: String Translation, Translation Management PHP version: 8.x (confirmed stable and supported by hosting) Hosting: cPanel-based environment Page builder: Elementor No custom code interacting with WPML hooks or filters Observations The error occurs during normal WordPress execution (admin and frontend) It sometimes coincides with WPML-related operations (translations, synchronization) Disabling WPML stops the error entirely (confirmed by testing) Questions Is this a known issue or regression in recent WPML versions? Are there known conflicts between WPML and Elementor that could trigger this recursion? Is there a recommended fix, patch, or workaround, or should we roll back to a specific stable WPML version? We are happy to provide: Full debug logs WPML debug information Temporary admin access if needed Thank you for your assistance — this issue is currently blocking stable operation of the site. Kind regards, Balázs
February 3, 2026 at 8:34 pm #17789574
Itamar WPML Supporter since 02/2016 Languages: English (English ) Timezone: Asia/Jerusalem (GMT+02:00)	Hi, I'm consulting our second-tier supporters about this issue and will update you here once I have their reply. Regards, Itamar.
February 4, 2026 at 9:09 am #17790417
dianaV-9	When can I expect some help with my 2 websites? It would be very important for the problem to be resolved and for me to finally be able to launch my ads. Because until my website is stable, I cannot run the ads.
February 4, 2026 at 9:23 am #17790436
dianaV-9	Dear Andrey, Thank you for your message. I have added and saved the required PHP 8.3 settings on both websites via cPanel (MultiPHP INI Editor): zend.max_allowed_stack_size = 256K zend.reserved_stack_size = 48K After applying the changes, I cleared all caches and retested, but the critical fatal error / infinite recursion issue still persists. Could you please advise on the next troubleshooting step (e.g., what logs or debug information you would like me to provide)? Best regards, Balazs
February 4, 2026 at 10:24 am #17790758
Itamar WPML Supporter since 02/2016 Languages: English (English ) Timezone: Asia/Jerusalem (GMT+02:00)	Hi, Balazs. I didn't provide the workaround you mentioned above. It was my colleague in another ticket you opened here: https://wpml.org/forums/topic/critical-fatal-error-infinite-recursion-in-wpml-confirmed-not-server-side-issue-2/. For your information, there is no need to open more than one ticket per issue. In any case, our second-tier supporter suggests trying the workaround in this errata: https://wpml.org/errata/php-8-3-x-fatal-error-maximum-call-stack-size-reached-due-to-possible-infinite-recursion/. For your convenience, the workaround is this: 1. Take a backup of the site in case something goes wrong. 2. Edit the php.ini file of your server. 3. Change the following lines to have the value of -1, like this: zend.max_allowed_stack_size = -1 zend.reserved_stack_size = -1 4. Save the changes. ** Important! Please make a full site backup (files and DB) before you proceed with those steps** Then check if those errors stop showing. Regards, Itamar.