libcxxabi on ARM/Linux

Project Infrastructure LLVM Dev List Archives
1

Hi,

I recently tried to build libcxxabi on ARM/Linux but looks like libunwind is not providing the necessary symbols needed, precisely _Unwind_SjLj_RaiseException and related functions are missing.

Did anyone have any success with this before?

Thanks,
ismail

2

I recently tried to build libcxxabi on ARM/Linux but looks like libunwind is
not providing the necessary symbols needed, precisely
_Unwind_SjLj_RaiseException and related functions are missing.

I've not tried it, but I'm very surprised that symbol is needed on
Linux. As far as I know only iOS uses the setjmp/longjmp
exception-handling style.

Of course, it could be a very poorly named but still generic function
(or an alias or something). But I'd still start my search by looking
into just what thinks it wants that and why.

Good luck!

Tim.

3

Hi Ismail,

ARM Linux shouldn't use SJLJ exception handling, but again, nor does EHABI
work yet, so you should be ok in disabling EH for now, if that helps you
build the library (I don't know).

Support for EHABI is coming a long way, and I hope we can have something,
even if basic, for the next release. But that doesn't help your problem,
and someone with more knowledge on the libcxx could chime in to help you.

cheers,
--renato

4

Hi,