[cfe-dev] libc++abi on linux

[Ben Pope]

On Monday, July 09, 2012 03:23 PM, Ashok Nalkund wrote:
> On 7/8/2012 11:12 PM, Ben Pope wrote:
>>> Would there be a recommendation on the different pieces (specifically
>>> ABI and the unwind libraries)?
>>
>> This is the crux of my question, really.  Since libc++abi has all the
>> boxes ticked for linux: http://libcxxabi.llvm.org/spec.html it's easy to
>> assume that there are no more pieces to the puzzle.  I'm sure Howard
>> didn't do the work just for the challenge itself.
>
> That was another reason for choosing libc++abi, it wasnt lacking
> anything in terms of features.

Well, except for the unwind stuff, but that seems intentional, despite 
there being no documented alternative.

> <snip>
>> It's frustrating, because I have managed to get it to work for a
>> small-ish project with quite a few dependencies (but subsequently broken
>> it), but I'm not sure if what I did to get it to work is likely to
>> continue to work with newer versions.
>
> I can post my steps to build clang with g++ and libc++ and use it to
> compile other code.

I'll probably just wait until Chandlers recent build stuff drops, and 
use CMake.  Frankly, I'm happy to have it built with GCC, it's probably 
faster, anyway.  I also found a .deb for Ubuntu (12.04) which appears to 
work, too, which is fine until I decide I want to move onto master 
again, but at the moment I'm happy on 3.1.

Due to all of this ABI/Unwind unknownness, I'm just using Clang to 
compile the code, I'm not that bothered about linking it or distributing 
it built that way, there just doesn't seem to be enough momentum around 
getting it to work on Linux right now.  It's a real shame.

> As I said earlier, compiling my code with
> clang/libc++ uses libstdc++ for ABI and unwind pieces (which I'm trying
> to remove). Even though your goal is different form mine, having a
> self-contained set of instructions to compile and use clang/libc++ will
> be helpful in general.

I don't think our goals are much different.  I just care less about how 
Clang is actually built.

Ben