mismatched types error on armv7

[MagaTailor]

Hi,

There's been a breakage affecting arm platforms recently (and x86 android too) and while some of the crates have already been fixed it seems the problem won't be fixed in a top-down manner. You will probably have to look into this:

Compiling users v0.4.3
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:280:40: 280:41 error: mismatched types:
 expected `*const u8`,
    found `*const i8`
(expected u8,
    found i8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:280     from_utf8_unchecked(CStr::from_ptr(p).to_bytes()).to_string()
                                                                                                                               ^
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:280:40: 280:41 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:365:61: 365:89 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:365                 let user = unsafe { passwd_to_user(getpwnam(username_c.unwrap().as_ptr())) };
                                                                                                                                                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:365:61: 365:89 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:418:62: 418:92 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:418                 let user = unsafe { struct_to_group(getgrnam(group_name_c.unwrap().as_ptr())) };
                                                                                                                                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/users-0.4.3/src/lib.rs:418:62: 418:92 help: run `rustc --explain E0308` to see a detailed explanation
error: aborting due to 3 previous errors

[MagaTailor]

The alternative to doing casts is a switch to std::os::raw where applicable. What's the plan for this crate?

[ogham]

Hi,

I just made a load of changes, including removing some casts (which I think I originally wrote when I didn't know what I was doing). Try now?

[MagaTailor]

It does compile on nightly - I can't tell from memory if it didn't using 1.5 or nightly.

[ogham]

This crate doesn't use any unstable features anymore, so if it compiles now it should compile everywhere (I hope!)

[MagaTailor]

No, that's not what I meant - the ARM issue bites differently before and after 1.6. The details are in the link.

[MagaTailor]

I've found my old comment so it seems the issue was not about 1.5 but rather >= 1.6. Thanks!

It doesn't help much building exa though, cause the root cause is still there and other crates, like locale stop the show.

[MagaTailor]

Ha, see what I mean? Before that debacle Rust used to be a cross-platform language but now you'd have to be thinking about stuff like this in advance:

 Compiling users v0.4.4
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:326:35: 326:44 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:326         members.push(from_raw_buf(*username));
                                                                                                                      ^~~~~~~~~
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:326:35: 326:44 help: run `rustc --explain E0308` to see a detailed explanation
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:365:61: 365:89 error: mismatched types:
 expected `*const u8`,
    found `*const i8`
(expected u8,
    found i8) [E0308]
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:365                 let user = unsafe { passwd_to_user(getpwnam(username_c.unwrap().as_ptr())) };
                                                                                                                                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:365:61: 365:89 help: run `rustc --explain E0308` to see a detailed explanation
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:418:62: 418:92 error: mismatched types:
 expected `*const u8`,
    found `*const i8`
(expected u8,
    found i8) [E0308]
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:418                 let user = unsafe { struct_to_group(getgrnam(group_name_c.unwrap().as_ptr())) };
                                                                                                                                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/tmp/.cargo-1.5/registry/src/github.com-48ad6e4054423464/users-0.4.4/src/lib.rs:418:62: 418:92 help: run `rustc --explain E0308` to see a detailed explanation
error: aborting due to 3 previous errors
Build failed, waiting for other jobs to finish...
Could not compile `users`.

This happens on Rust 1.5 which previously was OK.

[MagaTailor]

Rust 1.5 is probably irrelevant by now, closing.