Rust 1.6 breaks crate

[MagaTailor]

This issue has led to compilation errors:

Compiling sdl2_ttf v0.10.0
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:245:41: 245:57 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:245             let raw = ffi::TTF_OpenFont(cstring.as_ptr(), ptsize as c_int);
                                                                                                                                             ^~~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:245:41: 245:57 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:258:46: 258:62 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:258             let raw = ffi::TTF_OpenFontIndex(cstring.as_ptr(), ptsize as c_int, index as c_long);
                                                                                                                                                  ^~~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:258:46: 258:62 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:380:61: 380:66 error: mismatched types:
 expected `*const u8`,
    found `*const i8`
(expected u8,
    found i8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:380                 Some(String::from_utf8_lossy(CStr::from_ptr(cname).to_bytes()).to_string())
                                                                                                                                                                 ^~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:380:61: 380:66 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:392:61: 392:66 error: mismatched types:
 expected `*const u8`,
    found `*const i8`
(expected u8,
    found i8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:392                 Some(String::from_utf8_lossy(CStr::from_ptr(cname).to_bytes()).to_string())
                                                                                                                                                                 ^~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:392:61: 392:66 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:444:41: 444:55 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:444             ffi::TTF_SizeText(self.raw, ctext.as_ptr(), &w, &h)
                                                                                                                                             ^~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:444:41: 444:55 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:465:65: 465:80 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:465                             ffi::TTF_RenderText_Solid(self.raw, source.as_ptr(),
                                                                                                                                                                     ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:465:65: 465:80 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:469:66: 469:81 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:469                             ffi::TTF_RenderText_Shaded(self.raw, source.as_ptr(),
                                                                                                                                                                      ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:469:66: 469:81 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:473:67: 473:82 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:473                             ffi::TTF_RenderText_Blended(self.raw, source.as_ptr(),
                                                                                                                                                                       ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:473:67: 473:82 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:477:75: 477:90 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:477                             ffi::TTF_RenderText_Blended_Wrapped(self.raw, source.as_ptr(),
                                                                                                                                                                               ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:477:75: 477:90 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:487:65: 487:80 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:487                             ffi::TTF_RenderUTF8_Solid(self.raw, source.as_ptr(),
                                                                                                                                                                     ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:487:65: 487:80 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:491:66: 491:81 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:491                             ffi::TTF_RenderUTF8_Shaded(self.raw, source.as_ptr(),
                                                                                                                                                                      ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:491:66: 491:81 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:495:67: 495:82 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:495                             ffi::TTF_RenderUTF8_Blended(self.raw, source.as_ptr(),
                                                                                                                                                                       ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:495:67: 495:82 help: run `rustc --explain E0308` to see a detailed explanation
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:499:75: 499:90 error: mismatched types:
 expected `*const i8`,
    found `*const u8`
(expected i8,
    found u8) [E0308]
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:499                             ffi::TTF_RenderUTF8_Blended_Wrapped(self.raw, source.as_ptr(),
                                                                                                                                                                               ^~~~~~~~~~~~~~~
/home/odroid/.cargo/registry/src/github.com-48ad6e4054423464/sdl2_ttf-0.10.0/src/sdl2_ttf/lib.rs:499:75: 499:90 help: run `rustc --explain E0308` to see a detailed explanation
error: aborting due to 13 previous errors
Could not compile `sdl2_image`.

A mechanical cast as *const _ seems to be enough of a fix in most cases.
Rust 1.5 is still fine.

[MagaTailor]

So, what's the plan for this crate? You should either accept the corrected PR or state if a switch to std::os::raw is coming (where applicable).

[andelf]

I'll check this out tonight. sorry for the delay

[MagaTailor]

Have a look at Smithay/wayland-rs#42 ; it should be much better to not depend on libc.

[MagaTailor]

Fixed in master.