[Pkg-rust-maintainers] Bug#1043597: rust-mbox FTBFS on architectures where char is unsigned

[Adrian Bunk]

Source: rust-mbox
Version: 0.6.0-1
Severity: important
Tags: ftbfs
Forwarded: https://github.com/kennytm/mbox/pull/18/commits/82ab7559203a434a159d54f42b59ce9c901f7055
X-Debbugs-Cc: Emanuele Rocca <ema at debian.org>, Debian Rust Maintainers <pkg-rust-maintainers at alioth-lists.debian.net>

https://buildd.debian.org/status/fetch.php?pkg=rust-mbox&arch=arm64&ver=0.6.0-1&stamp=1691926211&raw=0

...
error[E0600]: cannot apply unary operator `-` to type `u8`
   --> src/sentinel.rs:331:26
    |
331 |         *src.offset(1) = -0x19;
    |                          ^^^^^ cannot apply unary operator `-`
    |
    = note: unsigned values cannot be negated

error[E0600]: cannot apply unary operator `-` to type `u8`
   --> src/sentinel.rs:332:26
    |
332 |         *src.offset(2) = -0x6c;
    |                          ^^^^^ cannot apply unary operator `-`
    |
    = note: unsigned values cannot be negated

error[E0600]: cannot apply unary operator `-` to type `u8`
   --> src/sentinel.rs:333:26
    |
333 |         *src.offset(3) = -0x4e;
    |                          ^^^^^ cannot apply unary operator `-`
    |
    = note: unsigned values cannot be negated

error[E0600]: cannot apply unary operator `-` to type `u8`
   --> src/sentinel.rs:345:26
    |
345 |         *src.offset(0) = -1;
    |                          ^^
    |                          |
    |                          cannot apply unary operator `-`
    |                          help: you may have meant the maximum value of `u8`: `u8::MAX`
    |
    = note: unsigned values cannot be negated
...