[llvm] Remove iOS 5 check for tailcalls on ARM (PR #133354)

[Jon Roelofs via llvm-commits]

jroelofs wrote:

> > A quick dig through the relevant radars suggests that the issue was lack of support in the dynamic linker prior to iOS 5. This is the correct version check in that context. I think the proper fix for https://github.com/llvm/llvm-project/issues/102053 is to add a diagnostic in clang for this case.
>
> Oh I see.

Wait, sorry, I misspoke. It was the static linker at the time that didn't support it, and support landed in `ld64-124.1` per rdar://9116044.

> Maybe the person making the commit didn't devices running iOS versions <5 to test on, and they added the 5.0 check just to be safe.

Not based on my readings of the related radars, but if it works for you, go for it. The last devices that even supported iOS 4 are well past their support horizon.



https://github.com/llvm/llvm-project/pull/133354