Disabling JIT in Safari 6 to workaround severe Javascript JIT bugs

Question

We found a severe problem with the interpretation of our Javascript code that only occurs on iOS 5/Safari 6 (then current iPad release) that we think is due to critical bug in t

Answer 1

IMO, the correct solution is to report the bug to Apple, then workaround it in your code (surely using a separate a = a + 1; statement will work, unless the JIT is even worse than you thought!). It does indeed suck, though. Here's a list of common things you can also try throwing in to the function to make it de-optimise and not use JIT:

• Exceptions
• 'with' statement
• using arguments object, e.g. arguments.callee
• eval()

The problem with those is if the Javascript engine is optimised to JIT them before they fix that bug, in which case you're back to crashing. So, report and workaround!