[Bug c/108678] New: Windows on ARM64 platform target aarch64-w64-mingw32

["brechtsanders at users dot sourceforge.net" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108678

            Bug ID: 108678
           Summary: Windows on ARM64 platform target aarch64-w64-mingw32
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: brechtsanders at users dot sourceforge.net
  Target Milestone: ---

Are there plans to support Windows (using MinGW-w64) on ARM64?

The triplet for this platform should be: aarch64-w64-mingw32

I'm trying to build natively on a Windows on ARM device (bootstrapping from
LLVM/CLang).

Since binutils 2.40 there some support for aarch64 COFF/PE format, and I
already built a working binutils with the following supported targets:

ld --help|sed -n "s/^.*supported targets: //p"
pe-x86-64 pei-x86-64 pe-bigobj-x86-64 elf64-x86-64 pe-i386 pei-i386 elf32-i386
elf32-iamcu pdb elf64-little elf64-big elf32-little elf32-big pe-bigobj-i386
pe-aarch64-little pei-aarch64-little srec symbolsrec verilog tekhex binary ihex
plugin

So it looks like pe-aarch64-little and pei-aarch64-little are listed.

I'm don't know if a pe-bigobj-aarch64-little is needed or if it will be
supported in the future.

My first attempt to get gcc (I tried with source tarball 12.2.0) to configure
was changing the following line in gcc/config.gcc:

i[34567]86-*-mingw* | x86_64-*-mingw*)

to:

i[34567]86-*-mingw* | x86_64-*-mingw* | aarch64-*-mingw*)

but then I get the following error:

Unknown tune used in --with-tune=generic

What needs to be changed to get past that?