[cfe-dev] Small patches to allow fully independent clang/llvm/compiler-rt/libc++

[Szabolcs Nagy via cfe-dev]

* Renato Golin via cfe-dev <cfe-dev at lists.llvm.org> [2015-10-14 17:20:54 +0100]:

> On 14 October 2015 at 14:47, C Bergström <cbergstrom at pathscale.com> wrote:
> > (Barring libc, but that's typically future compatible. I've tested
> > this all the way back to SLES10)
> 
> I've been told Musl (http://www.musl-libc.org/) works well as a glibc
> replacement for OpenEmbedded on AArch64, and it even interoperates
> better than expected with libc++.
> 
> Not sure about the other targets, but may be worth considering.
> 


note that clang + compiler-rt does not work out of the box with musl because

freestanding code (such as the libc) cannot explicitly request the
compiler-rt after -nostdlib.

e.g. on gcc -lgcc [-lgcc_eh] works, on pcc `pcc --print-file-name=libpcc.a`
works, on clang nothing works so musl configure fails to detect it and
falls back to -lgcc. (compiler runtime has to be linked into libc.so)