Sudden raft of "Declaration of...should be compatible with..." errors

bunner_bob

I've been getting a lot of errors like:
Declaration of listText::setText() should be compatible with that of listBase::setText()

I understand why it's happening (default parameters in child class function must match parameters in parent class function), but I don't understand why I've never seen this before and why all of a sudden I'm getting so many from sites hosted at Pair Networks.

I asked and they haven't recently upgraded their PHP installations - but I'm suspecting maybe they have, and something is set differently in the new installation.

Does anyone know if a recent release of PHP now comes with something enabled by default that would make these errors appear? Perhaps an incremental update?

Also - the pages concerned still seem accessible. Should I worry about it? Are things no longer working as they should be, and I just haven't discovered how yet...?

NogDog

Could be a change in either the [man]error_reporting[/man] or [man]display_errors[/man] setting.

bunner_bob

Display Errors is off (these are via a log file).

Error reporting is 6135, which I thought is the "default" error reporting, which seems like E_ALL ^ E_NOTICE - and I didn't change anything...so should I be seeing these? I thought STRICT had to be enabled.

NogDog

Do the messages say they are "strict" or "notice" warnings?

Also note that the error reporting settings can be changed locally via .htaccess or per script, just in case either is a possibility.

bunner_bob

Don't seem to be either...here's another, from another Pair account (3rd site now in the last 2 days):

Error (2048): Declaration of deleteImage::deleteItem() should be compatible with that of deleteBase::deleteItem()

Weedpacket

That's a STRICT-level message (2048).

NogDog

Any chance they upgraded to PHP6? According to the manual, E_STRICT becomes included in E_ALL as of PHP6.0.

bunner_bob

Actually they seem to be upgrading to PHP 5.2.10 - that seems to be the culprit. Must have different settings out of the box.

bunner_bob

I guess I'm happy that I'm getting more comprehensive errors. Just that I never knew this was an issue (that you aren't supposed to overload methods) and so I did it all over the place. Could mean years worth of sites to fix...

How big a deal is it? We're talking about a base class with method foo() and descendant class with method foo($parameter) - for example. Everything seems to have worked fine until now, and seems to still be working after the 5.2.10 upgrade. I just get errors now.

Weedpacket

bunner bob wrote:
How big a deal is it?

Well, the principle (it's got a name but I forget it right now) is that any place that an instance of the base class can appear is a place where an instance of any child class could appear. If their methods have different signatures then that's no longer the case. You can't, for example, use if($thing instanceof BaseClass) to check that $thing has the interface it needs to have. You start having to pick over all the places where you use $thing and keep checking whether foo() has one parameter or two and that spoils a big part of the point of using inheritance in the first place.