The host simply does not understand the purpose of that function. Disabling it actually makes the issue they are trying to resolve worse.

Note that wordpress will also fail if that function is disabled

I have looked through the Joomla code and see that most calls are preceded by @ but one instance checks for the existence of the function

Is that inconsistent?

Is that inconsistent?

No. If it's accepted that set_time_limit() is the kind of function that could be disabled (which is very sensible for shared hosting), all instances should be wrapped in in function_exists() checks while still maintaining error suppression. This is because in PHP 8 calling a disabled function throws an Error which can not be suppressed, only caught. Previously only a warning was emitted.

so is set_time_limit() wrapped in function_exists() ? If not is that what is causing the issue?

Yes, that's what's causing the issue.

So why has nobody edited the code in Joomla so thatset_time_limit() is wrapped in function_exists() ?

Could be it was not reported before that there are issues like this my hoster for example also dont block that. Feel free to create a PR or look where that calles are missing so someone else can take a look and do the PR :)

#38876 (comment)
#38876 (comment)

2cents:

• Core code is trying to suppress the error by a nowadays unreliable/useless/error throwing @ to avoid using class_exists(). Means: Programmers were aware that not all hosts support set_time_limit() and that it is just a nice-to-have at this code place.
• It's a Joomla bug that it doesn't work anymore like before.
• If we leave it as it is, set_time_limit() should have been documented as a technical requirement of J!4.
  • Joomla should not expect that hosts will change their server configuration.
  • As long as we are talking about easily to fix things we shouldn't tell users that they have to change their hosting service.
• For the sake of consistency and code clarity @ should be replaced in core code at several places.

BTW: Using set_time_limit() at this code place is a bit questionable from my point of view.

... Feel free to create a PR or look where that calles are missing so someone else can take a look and do the PR :)

If I could I would but that is beyond me.

see #41523