New comment by ericonr on void-packages repository

https://github.com/void-linux/void-packages/pull/28439#issuecomment-779625380

Comment:
```
error[E0308]: mismatched types
  --> packages/hurl/src/runner/xpath.rs:88:45
   |
88 |             let x = unsafe { CStr::from_ptr(c_s2) };
   |                                             ^^^^ expected `u8`, found `i8`
   |
   = note: expected raw pointer `*const u8`
              found raw pointer `*const i8`
```

They don't test builds for ARM, this should have been detected a long while ago. Please report to upstream. chars have different default signedness on different platforms, so they should be using `c_char` from `std::os` or `libc`, not `u8` or `i8`.