New comment by kwshi on void-packages repository

https://github.com/void-linux/void-packages/pull/35624#issuecomment-1152441085

Comment:
> > I've applied @hasufell's patch and gotten the build to work; compilation on/to non-`x86_64` architectures or musl unfortunately doesn't work currently because some of ghcup's dependencies are incompatible (e.g., haskell's `libarchive` package explicitly imports a glibc header).  This package template is ready for review.
> 
> That can't be. The ghcup binaries are built on alpine linux with musl.
> 
> There's a static libarchive option: `-f-system-libarchive`

Weird-- I've tried building with `-f-system-libarchive` and the error still appears. The relevant error message, I think, is
```
c/archive_platform.h:84:10: error:
     fatal error: sys/cdefs.h: No such file or directory
       84 | #include <sys/cdefs.h>
          |          ^~~~~~~~~~~~~
   |
84 | #include <sys/cdefs.h>
```
Where all googled instances of `sys/cdefs.h` seem to point to GNU libc.  The full error log on the workflow run is at https://github.com/void-linux/void-packages/runs/6742127441?check_suite_focus=true (`x86_64-musl` architecture run).

I'll do some more investigation to see what's going on.