Nick Desaulniers [off-list ref] writes:

On Thu, Jun 11, 2020 at 4:53 PM Segher Boessenkool
[off-list ref] wrote:

quoted

On Thu, Jun 11, 2020 at 03:43:55PM -0700, Nick Desaulniers wrote:

quoted

Segher, Cristophe, I suspect Clang is missing support for the %L and %U
output templates [1].

...

IIUC the bug report correctly, it looks like LLVM is failing for the
__put_user_asm2_goto case for -m32.  A simple reproducer:
https://godbolt.org/z/jBBF9b

If you add `-mregnames` you get register names:

https://godbolt.org/z/MxLjhF

foo:
        stw %r3, 0(%r5)
        stw %r4, 4(%r5)
        blr


cheers