[WIP] bump nix to 0.14 to fix libc issues

[ryankurte]

Waiting on: nix-rust/nix#1060 (comment)
See also: rust-embedded/linux-embedded-hal#17

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @posborne (or someone else) soon.

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[ryankurte]

this, looks like it's gonna need some updating...

error: cannot find macro `ioctl!` in this scope
   --> src/spidevioctl.rs:126:5
    |
126 |     ioctl!(read get_mode_u8 with SPI_IOC_MAGIC, SPI_IOC_NR_MODE; u8);
    |     ^^^^^

error[E0425]: cannot find function `set_mode_u32` in module `ioctl`
   --> src/spidevioctl.rs:164:46
    |
164 |         try!(from_nix_result(unsafe { ioctl::set_mode_u32(fd, &mode.bits) }));
    |                                              ^^^^^^^^^^^^ not found in `ioctl`

error[E0425]: cannot find function `set_mode_u8` in module `ioctl`
   --> src/spidevioctl.rs:167:46
    |
167 |         try!(from_nix_result(unsafe { ioctl::set_mode_u8(fd, &bits) }));
    |  

error[E0425]: cannot find function `get_lsb_first` in module `ioctl`
   --> src/spidevioctl.rs:174:42
    |
174 |     try!(from_nix_result(unsafe { ioctl::get_lsb_first(fd, &mut lsb_first) }));
    |                                          ^^^^^^^^^^^^^ not found in `ioctl`
help: possible candidate is found in another module, you can import it into scope
    |
11  | use spidevioctl::get_lsb_first;
    |

...

[posborne]

@ryankurte I can take a look at resolving this. I'm a a maintainer on nix and the original author of some of the ioctl abstrations. There were some changes in recent versions that change the macros. Should be easy enough to address to get to 0.14.

[ryankurte]

closing in favour of #16