The Effective Power Bug: Why Can Weird Text Crash Your iPhone?

[adityakhanna]

So, the iPhone basically commits some sort of suicide because it's confused...

"iPhone is confused
iPhone hurt itself in confusion"

[coolbrotherf]

I know it's been 7 years since this video, but one thing I never saw anyone mention was that it combines right to left and left to right text in one message. When trying to shorten a message, the phone sets the text direction to left to right with the English words, but half way through it switches to right to left with Arabic text. That means it was probably trying to shorten the Arabic text backwards and causing some kind of crash trying to delete text out of bounds if the intended memory address.

[Wizzerzak]

If this is the case I wonder if Arabic speaking users of iPhones have this problem regularly.

[kriscodangus]

"But what do I know" ... Pretty much everything man.

[alanhere]

I can imagine a loop of repeatedly adding and removing a character, and testing for length, attempting to iterate to a suitable length.

Or getting a negative number for how much length adding a character contributed where only positive numbers are supposed to occur.

[sporkafife]

I think we all know that Apple are just going to say "here, it's fixed!" without any explanation. This is a bit of a shame really, as if they revealed something about the nature of this crash, it might be a good way to teach people about writing code that handles many different languages.

[ninjaed]

I've seen some people claim that it's ISIS hacking your phone >.> some people are so computer illiterate it hurts.

[wyatt]

somebody tried to send me this but I have android

[SuperFranzs]

You have no idea how fun this is for an Android user.

[opalpersonal]

6 year old tom scott: this is a really interesting bug for this reason, but don't worry, it will likely be patched soon!
me 6 years later: * sad that i can't replicate the bug *

[ArchaicMuse]

Would rotating your phone in landscape mode prevent the appearance of that bug ? (notification band being longer)

[BEASTXDGAMER]

big example on more than one shape of a letter in Arabic is the letter "ه" :
هـ in the beginning of a word
ـهـ between letters
ـه at the end of a word
ه after non connective letter

[Lutranereis]

Once you mentioned deleting text, I knew where you were going with Arabic, it all clicked into place. This has to be one of the most plausible explanations I've heard.

[Keenath]

I'm betting a combination of the mixed languages and weird resizing makes the phone inadvertently walk off the end of the character array, which usually - but not always - causes a segmentation fault. Occasionally it didn't blow up because there just happens to be valid text or a termination character in that next memory location.

[bruhbruh]

The Arabic text literally says “llsbllsbrr”

[noobyjohn]

I have learned more from you than a day at Computer coding class.

[mudkiptg]

iPhone 8: You can finally render some Arabic texts!

[transbiologistthetransesto]

"effective. Power" makes it sound like we're casting a spell

[mj]

I forgot to tell you that we at apple devs say thank you for doing our debugging for us. We didn't even have to do any work. We watched this and tested the issue. Bang on. Thanks

[aimenbarigoudz]

Regarding your question about the Arabic script pattern you found, yes that comes up in almost every word as the way we connect letters can make the letters appear a different size for certain letters such as ت as you showed.