Rust is available!
Using -Oline -j 72 W=1 redirect to  and 
LLVM=1 cc=clang
clang version 20.1.6 (Fedora 20.1.6-1.fc42)
rustc 1.87.0 (17067e9ac 2025-05-09) (Fedora 1.87.0-2.fc42)
Tree base:
ccf522b918f9 ("Use unqualified references to ffi types")
Baseline building the tree
  GEN     Makefile
#
# configuration written to .config
#
  GEN     Makefile
#
# configuration written to .config
#
  SYNC    include/config/auto.conf
  GEN     Makefile
  GEN     Makefile
  DESCEND objtool
  CALL    ../scripts/checksyscalls.sh
  INSTALL libsubcmd_headers
  RUSTC L rust/kernel.o
  EXPORTS rust/exports_kernel_generated.h
  CC      rust/exports.o
  AR      rust/built-in.a
  RUSTC [M] mm/kasan/kasan_test_rust.o
  LD [M]  mm/kasan/kasan_test.o
  RUSTC [M] drivers/net/phy/ax88796b_rust.o
  CHK     kernel/kheaders_data.tar.xz
  AR      built-in.a
  AR      vmlinux.a
  LD      vmlinux.o
  OBJCOPY modules.builtin.modinfo
  GEN     modules.builtin
  MODPOST Module.symvers
  UPD     include/generated/utsversion.h
  CC      init/version-timestamp.o
  KSYMS   .tmp_vmlinux0.kallsyms.S
  AS      .tmp_vmlinux0.kallsyms.o
  LD      .tmp_vmlinux1
  NM      .tmp_vmlinux1.syms
  KSYMS   .tmp_vmlinux1.kallsyms.S
  AS      .tmp_vmlinux1.kallsyms.o
  LD      .tmp_vmlinux2
  NM      .tmp_vmlinux2.syms
  KSYMS   .tmp_vmlinux2.kallsyms.S
  AS      .tmp_vmlinux2.kallsyms.o
  LD      vmlinux.unstripped
  NM      System.map
  SORTTAB vmlinux.unstripped
  RSTRIP  vmlinux
  GEN     modules.builtin.ranges
  CC      arch/x86/boot/version.o
  RELOCS  arch/x86/boot/compressed/vmlinux.relocs
  OBJCOPY arch/x86/boot/compressed/vmlinux.bin
  LD [M]  mm/kasan/kasan_test.ko
  CC      arch/x86/boot/compressed/kaslr.o
  VOFFSET arch/x86/boot/compressed/../voffset.h
  CC      arch/x86/boot/compressed/misc.o
  LD [M]  drivers/net/phy/ax88796b_rust.ko
  GZIP    arch/x86/boot/compressed/vmlinux.bin.gz
  MKPIGGY arch/x86/boot/compressed/piggy.S
  AS      arch/x86/boot/compressed/piggy.o
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  OBJCOPY arch/x86/boot/vmlinux.bin
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  BUILD   arch/x86/boot/bzImage
Kernel: arch/x86/boot/bzImage is ready  (#9)
Building the tree before the patch
  GEN     Makefile
#
# configuration written to .config
#
  GEN     Makefile
#
# configuration written to .config
#
  SYNC    include/config/auto.conf
  GEN     Makefile
  GEN     Makefile
  DESCEND objtool
  CALL    ../scripts/checksyscalls.sh
  INSTALL libsubcmd_headers
  RUSTC L rust/kernel.o
  EXPORTS rust/exports_kernel_generated.h
  CC      rust/exports.o
  AR      rust/built-in.a
  RUSTC [M] mm/kasan/kasan_test_rust.o
  LD [M]  mm/kasan/kasan_test.o
  RUSTC [M] drivers/net/phy/ax88796b_rust.o
  CHK     kernel/kheaders_data.tar.xz
  AR      built-in.a
  AR      vmlinux.a
  LD      vmlinux.o
  OBJCOPY modules.builtin.modinfo
  GEN     modules.builtin
  MODPOST Module.symvers
  UPD     include/generated/utsversion.h
  CC      init/version-timestamp.o
  KSYMS   .tmp_vmlinux0.kallsyms.S
  AS      .tmp_vmlinux0.kallsyms.o
  LD      .tmp_vmlinux1
  NM      .tmp_vmlinux1.syms
  KSYMS   .tmp_vmlinux1.kallsyms.S
  AS      .tmp_vmlinux1.kallsyms.o
  LD      .tmp_vmlinux2
  NM      .tmp_vmlinux2.syms
  KSYMS   .tmp_vmlinux2.kallsyms.S
  AS      .tmp_vmlinux2.kallsyms.o
  LD      vmlinux.unstripped
  NM      System.map
  SORTTAB vmlinux.unstripped
  RSTRIP  vmlinux
  GEN     modules.builtin.ranges
  CC      arch/x86/boot/version.o
  RELOCS  arch/x86/boot/compressed/vmlinux.relocs
  OBJCOPY arch/x86/boot/compressed/vmlinux.bin
  CC      arch/x86/boot/compressed/kaslr.o
  VOFFSET arch/x86/boot/compressed/../voffset.h
  CC      arch/x86/boot/compressed/misc.o
  GZIP    arch/x86/boot/compressed/vmlinux.bin.gz
  MKPIGGY arch/x86/boot/compressed/piggy.S
  AS      arch/x86/boot/compressed/piggy.o
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  OBJCOPY arch/x86/boot/vmlinux.bin
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  BUILD   arch/x86/boot/bzImage
Kernel: arch/x86/boot/bzImage is ready  (#10)
  LD [M]  mm/kasan/kasan_test.ko
  LD [M]  drivers/net/phy/ax88796b_rust.ko
Building the tree with the patch
  GEN     Makefile
#
# configuration written to .config
#
  GEN     Makefile
#
# configuration written to .config
#
  SYNC    include/config/auto.conf
  GEN     Makefile
  GEN     Makefile
  DESCEND objtool
  CALL    ../scripts/checksyscalls.sh
  INSTALL libsubcmd_headers
  RUSTC L rust/kernel.o
  EXPORTS rust/exports_kernel_generated.h
  CC      rust/exports.o
  AR      rust/built-in.a
  RUSTC [M] mm/kasan/kasan_test_rust.o
  LD [M]  mm/kasan/kasan_test.o
  RUSTC [M] drivers/net/phy/ax88796b_rust.o
  CHK     kernel/kheaders_data.tar.xz
  AR      built-in.a
  AR      vmlinux.a
  LD      vmlinux.o
  OBJCOPY modules.builtin.modinfo
  GEN     modules.builtin
  MODPOST Module.symvers
  UPD     include/generated/utsversion.h
  CC      init/version-timestamp.o
  KSYMS   .tmp_vmlinux0.kallsyms.S
  AS      .tmp_vmlinux0.kallsyms.o
  LD      .tmp_vmlinux1
  NM      .tmp_vmlinux1.syms
  KSYMS   .tmp_vmlinux1.kallsyms.S
  AS      .tmp_vmlinux1.kallsyms.o
  LD      .tmp_vmlinux2
  NM      .tmp_vmlinux2.syms
  KSYMS   .tmp_vmlinux2.kallsyms.S
  AS      .tmp_vmlinux2.kallsyms.o
  LD      vmlinux.unstripped
  NM      System.map
  SORTTAB vmlinux.unstripped
  RSTRIP  vmlinux
  GEN     modules.builtin.ranges
  CC      arch/x86/boot/version.o
  RELOCS  arch/x86/boot/compressed/vmlinux.relocs
  OBJCOPY arch/x86/boot/compressed/vmlinux.bin
  CC      arch/x86/boot/compressed/kaslr.o
  VOFFSET arch/x86/boot/compressed/../voffset.h
  CC      arch/x86/boot/compressed/misc.o
  LD [M]  mm/kasan/kasan_test.ko
  LD [M]  drivers/net/phy/ax88796b_rust.ko
  GZIP    arch/x86/boot/compressed/vmlinux.bin.gz
  MKPIGGY arch/x86/boot/compressed/piggy.S
  AS      arch/x86/boot/compressed/piggy.o
  LD      arch/x86/boot/compressed/vmlinux
  ZOFFSET arch/x86/boot/zoffset.h
  OBJCOPY arch/x86/boot/vmlinux.bin
  AS      arch/x86/boot/header.o
  LD      arch/x86/boot/setup.elf
  OBJCOPY arch/x86/boot/setup.bin
  BUILD   arch/x86/boot/bzImage
Kernel: arch/x86/boot/bzImage is ready  (#11)