llvm dev - Oct 2015 - [libunwind][Mips] Problem using gas to assemble UnwindRegistersSave.S

> > Should the integrated assembler be enabled by default for the Mips?
> 
> Not yet. There's a number of quiet mis-assembly bugs at the moment. The
> plan is to switch it on once it's good enough for the Linux kernel and
see what
> bug reports come back.
Having said this, we had our first successful boot of the Linux kernel build
with clang and -fintegrated-as today.

On 09/30/2015 05:48 AM, Daniel Sanders wrote:
>>> Should the integrated assembler be enabled by default for the Mips?
>> Not yet. There's a number of quiet mis-assembly bugs at the moment.
The
>> plan is to switch it on once it's good enough for the Linux kernel
and see what
>> bug reports come back.
> Having said this, we had our first successful boot of the Linux kernel
build with clang and -fintegrated-as today.
>
Very cool!

-Rich

On 09/30/2015 05:48 AM, Daniel Sanders wrote:
>>> Should the integrated assembler be enabled by default for the Mips?
>> Not yet. There's a number of quiet mis-assembly bugs at the moment.
The
>> plan is to switch it on once it's good enough for the Linux kernel
and see what
>> bug reports come back.
> Having said this, we had our first successful boot of the Linux kernel
build with clang and -fintegrated-as today.
>
Today just for fun I built clang/LLVM, libc++, libc++abi, libunwind, 
musl, binutils, and GDB for Mips
using the integrated assembler. It seemed to work flawlessly.
Now I'm trying to use the newly built tools to build themselves again. 
So far so good, but it will take
a while because I have to run the tools using QEMU Linux user space 
emulation.

-Rich

Hi Rich,
> Today just for fun I built clang/LLVM, libc++, libc++abi, libunwind,
> musl, binutils, and GDB for Mips using the integrated assembler
I've tried something similar but I used LLD, LLDB and the builtins library
from compiler-rt. Static builds were running fine but there are still
some small issues with shared linking which I'm trying to resolve.

I just want to clarify that libunwind isn't really supported on MIPS at the
moment. Here's the message from the commit (r248673) that enabled the
building
of libunwind for MIPS:

   Currently, libunwind doesn't support MIPS. However, with this patch
   we do allow the library to build, and we warn the user about the lack of
   support for MIPS. Also, the dummy unw_getcontext() implementation for MIPS
just
   traps on function entry in order to avoid any confusion with silent/weird
   failures at runtime.

   This allows us to test an LLVM-based toolchain without the dependency on a
   GCC toolchain. Of course, C++ exception handling and other things that depend
   on stack unwinding will not work until we add a proper implementation of the
   stub functions.

- Vasileios