Hi Christophe,
Here are the commits, in order, that Adhemerval did to support 48-bit VMA on AArch64.
r275792: [asan] Enable 48-bit VMA support on aarch64 r277137: tsan: Enable 48-bit VMA support on aarch64 r279752: msan: Enable 48-bit VMA support on aarch64 r279753: dfsan: Enable 48-bit VMA support on aarch64
Currently, all sanitiser tests pass on Ubuntu Xenial on the LLVM side.
cheers, --renato