New comment by mintsuki on void-packages repository

https://github.com/void-linux/void-packages/pull/31658#issuecomment-869008021

Comment:
> Building a full gcc toolchain will end painfull. You can try to use add `cross-x86_64-linux-gnu` for `i686*` and `x86_64-musl` builds. (I initial forgot that we have it available on `i686` nowadays).
> 
> So you can add this after checksum
> 
> ```shell
> case "$XBPS_TARGET_MACHINE" in
>         x86_64);;
>         *) hostmakedepends+=" cross-x86_64-linux-gnu";;
> esac
> ```
> 
> and this as do_build
> 
> ```shell
> do_build() {
>         if [ "$XBPS_TARGET_MACHINE" = "x86_64" ]; then
>                 make
>         else
>                 CFLAGS="" make CROSS_COMPILE="x86_64-linux-gnu-" \
>                         CC="x86_64-linux-gnu-gcc" TOOLCHAIN="x86_64-linux-gnu" \
>                         CC_TOOLCHAIN="x86_64-linux-gnu-gcc"
>                 make bin/limine-install TOOLCHAIN="x86_64-linux-gnu"
>         fi
> }
> ```
> 
> The build system does all kinds of wonky assumptions, this should workaround most/all of them.

It needs a cross compiler on musl too, or alternatively an implementation of `stdint.h` that works. Using the provided cross compiler would be ideal.

The cross compiler *does* build, and check the CI, everything else builds fine too, except `i686` where I assume the build system passes `-mtune=i686` to the CFLAGS when it should not do that as it will break stuff.

This can also easily be worked around by just unsetting the `CFLAGS` or stripping out the `-mtune` flag from them.