On Fri, Nov 3, 2017 at 2:42 PM, Will Deacon [off-list ref] wrote:

We used to link against libgcc way back when, but that dependency was
removed in commit d67703a8a69e ("arm64: kill off the libgcc dependency")
and I'm really not keen to add it back. I also think that there might
be licensing concerns if you link against it and make use of GCC plugins,
but IANAL.

Considering many other architectures link to it, that seems strange to me...

Shouldn't we just provide our own implementations of __ashlti3 and
__ashrti3 instead?

I just coded up an implementation. I'm testing it now and I'll have v3
for you shortly.

Jason