LTO & aarch64

[John Pullen <john@xxxxxxxxxxxxxxxxxxxxxx>]

Hi all,

I'm using the latest GCC 7.1 source which I've built locally for 
aarch64. Everything works fine, but I'm running into issuses using LTO.

Normally I compile our dynamic library with -ffixed-x18 and it works 
fine, but with LTO enabled, register x18 is used in the output assembler.

Is there anyway to stop LTO from using certain registers?

Cheers,
John.