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Your LimeSurvey version: LimeSurvey Community Edition Versión 5.4.10+221107
Own server or LimeSurvey hosting: Server Debian 11, Varnish, MySQL 5.5, PHP 8
Survey theme/template:
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We have set up a new server with the configuration: Server Debian 11, Varnish, MySQL 5.5, PHP 8

We have imported the surveys that were working correctly in LimeSurvey 3.25.15+210223 and when entering the survey for the first time by clicking on the survey title link, the error occurs:

Error 500:
round(): Argument #1 ($num) must be of type int|float, string given

However, by clicking on the "general settings and texts" icon to the left of the title, you can enter and the survey can be administered correctly. This error is reproduced a few times until you log out and log in again and then it disappears.

It also occurs in user surveys, almost always at the end, on the last screen.

We have seen questions in forums about this error for other similar applications (moodle, wordpress, drupal, etc.) and it seems that all agree that they are incompatibilities of the application with PHP8, mainly due to lack of development.

Does anyone have experience with this error in LimeSurvey 5?

Thanks and best regards
 

roblej wrote:

Your LimeSurvey version: LimeSurvey Community Edition Versión 5.4.10+221107
 

You're are using an outdated build of LimeSurvey 5,
Before investigating the issue I would recommend to update to a new LS5 build and check again.
What exact version of PHP 8 is used?

Aftre update to last 5

Please : report the issue, i'm sure it still exist in last version.

PS : and deactivate debug mode

Thank you very much, jelo and Denis

Jelo: still waiting the answer of hosting provider about the exact versión of PHP

Denis: you mean this in config.php file?

'config'=>array(
'debug'=>0,
'debugsql'=>0,
)

thanks again

Yes,

It's already on debug=>0 ?

Yes, it was already 0.

on the development server, we have upgraded to LimeSurvey 5.6.26+230613 via comfort update and we have verified that the degug mode settings were set to 0

PHP version is 8.0.20

should we put a lower PHP version? which version do you recommend?

You can upload a sample lss file with this issue ?

8.0.20 (and 8.1) MUST work : issue to be reported.

Maybe test if you have issue with 7.4.

Thank you very much for you answer. I would prefer not to make the survey public because it is a development for an institutional client, but I can send it to you by mail if you provide me with a means to do so, such as an email account.

You can send me your address to ikanosad20@gmail.com

But I already suspect that the problem has to do with the database limit. I uploaded the survey to my limesurvey.org account and got the same error.

The survey has these dimensions, although most of them are conditional questions depending on the user's profile:

Languages: 2
Groups of questions: 30
Questions: 639
Question attributes: 9466
Options: 134
Sub-questions: 2127

Maybe you can test just using a copy of survey and remove all unrelated question ?

After : you can update he sentence to put some Lore Ipsum.

[edit]
PS : you have 2 separate issue here  Sub-questions: 2127  : yes DB limit
But still such issue are related to such other issue :  github.com/LimeSurvey/LimeSurvey/pull/3214
Using cont(null) in Expression Manager don't break with 7.4 but with 8.0

 

Thanks again, Denis.

As you suggested, we have replaced the texts with lorem ipsum. We uploaded the complete survey file and a user's file already with the profile label. Only a certain number of items are shown to each profile.

We are taken a look to the "cont(null)" issue, because we do not realize clearly what do you mean.

Thanks a lot

roblej wrote:

We are taken a look to the "cont(null)" issue, because we do not realize clearly what do you mean.
 

It's because PHP8 broke with this.
And with Expressin manager : we doln't check if the data are an array or not before using it.

It's a LimeSurvey issue, except move to 7.4 : no way to fix it currently.