https://bugs.winehq.org/show_bug.cgi?id=38719
--- Comment #3 from André H. nerv@dawncrow.de --- (In reply to Anastasius Focht from comment #2)
Hello André,
unfortunately it's the 64-bit ELF loader that trashes register X18 during symbol resolving.
...
A safe solution would be to rebuild the aarch64 toolchain with '-ffixed-x18' enabled by default along with glibc (or better whole userland).
Maybe safe, but also very user unfriendly as long as it's not upstream...