On 1/29/26 11:31 PM, Nathan Chancellor wrote:
Hi Link,
On Thu, Jan 29, 2026 at 11:55:46AM +0100, Link Mauve wrote:
I’m trying to build the kernel for the Nintendo Wii, using LLVM instead
of gcc, in order to bring Rust support to this architecture (and also
because my distribution doesn’t ship a cross-compiling gcc), but I get
this build issue near the end:
```
% make O=wii LLVM=1 ARCH=powerpc -j1
make[1]: Entering directory '/home/linkmauve/dev/linux/wii'
GEN Makefile
CALL ../scripts/checksyscalls.sh
DESCEND objtool
INSTALL libsubcmd_headers
WRAP arch/powerpc/boot/dtbImage.wii
objcopy: Unable to recognise the format of the input file `vmlinux'
make[3]: *** [../arch/powerpc/boot/Makefile:394:
arch/powerpc/boot/dtbImage.wii] Error 1
make[2]: *** [../arch/powerpc/Makefile:236: zImage] Error 2
make[1]: *** [/home/linkmauve/dev/linux/Makefile:248: __sub-make] Error 2
make[1]: Leaving directory '/home/linkmauve/dev/linux/wii'
make: *** [Makefile:248: __sub-make] Error 2
```
I believe it should use $(OBJCOPY) instead of objcopy, which is set to
llvm-objcopy, but couldn’t figure out where it is misconfigured.
Thanks for your help!
It is the arch/powerpc/boot/wrapper script:
https://github.com/ClangBuiltLinux/linux/issues/1601
I have a WIP series from long ago that may be a good starting point for
getting something working but there were some errors I never got around
to solving before having to shelve it for other issues:
https://git.kernel.org/pub/scm/linux/kernel/git/nathan/linux.git/log/?h=wip/llvm-1-powerpc-boot-wrapper
Maybe something I (or someone else) can get back to soon.
Cheers,
Nathan
Hi Nathan,
your last 3 patches on this branch do indeed fix the wrapper script for
the cross-compilation with LLVM=1 ARCH=powerpc without CROSS_COMPILE set
or GNU binutils in PATH. They look good to me! Would you be willing to
submit them now without touching the VDSO? That part does not seem to be
necessary to fix the wrapper script for this usecase, so it should
strictly be an improvement. I'd also be happy to pick up your patches,
send them and follow-up on feedback if you don't want to do it yourself.
Best regards,
Aelin
