[cfe-dev] [libcxxabi] Contributing ARM EHABI support for libcxxabi

[Howard Hinnant]

On Dec 3, 2013, at 5:32 PM, Nico Weber <thakis at chromium.org> wrote:

> Hi,
> 
> We’re evaluating using libc++ and libc++abi for Chromium/Android. While libc++abi has an unwind implementation since r192136, we noticed that there’s no support for unwinding using ARM EHABI-style unwind information, so in the last two weeks some of us (Albert Wong, Antoine Labour, Dana Jansens, and I) prototyped support for it, and we’re able to catch at least simple exceptions (you can look at our code here [1]). We believe at least some of our code is ready for upstreaming.
> 
> A few questions:
> 1.) Is there interest for this upstream?
> 2.) Who should review this? Howard? Nick? Anton?
> 3.) r192136 didn’t add any test – how should testing of unwinding code work? Is running the exception tests in the libc++ suite enough?

I think at a minimum this should be done.  I'm assuming you mean the libc++abi suite.  No doubt the tests could be improved as well if you hit issues that are not currently tested.

Howard

> 4.) The unwind code doesn’t adhere to llvm style all that much – does it make sense to clang-format while it still has next to no svn history before landing other changes?
> 
> Thanks,
> Nico
> 
> [1]: https://github.com/awong-dev/ndk/tree/use-libc%2B%2Babi/sources/cxx-stl/llvm-libc%2B%2Babi/libcxxabi