Add some posix_spawn apple extension flags

Revert "Link to libgcc when statically linking musl"

This causes linker errors due to duplicated symbols. See https://github.com/rust-lang/rust/pull/52157

This reverts commit 920cfeac.

Add MODULE_INIT_ constants

These are flags required to implement the linux kernel loading mechanism.
Specifically finit_module.

These are flags required to implement the linux kernel loading mechanism.
Specifically finit_module.

Implement statfs for dragonfly, freebsd and openbsd

Openbsd fix

put in several fixes for OpenBSD (one fix per commit).
testsuite ran on OpenBSD 6.3-current (upcoming 6.4)

```
RUNNING ALL TESTS
PASSED 6474 tests
```

they doesn't exists on OpenBSD. put them under NetBSD specific tree.

Fix netbsd build with "stdbuild"

A bug was introduced in #930 which caused netbsd to not link to libm.

r? @alexcrichton

Fix a #[cfg] attribute

It looks like this was a mistake of #930 but should be easy to fix!

It looks like this was a mistake of #930 but should be easy to fix!

Link to libgcc when statically linking musl

On some architectures (e.g. aarch64) musl depends on some libgcc functions (`__addtf3`, `__multf3`, `__subtf3`) for `long double` arithmetic that it uses internally. Unfortunately we don't provide these functions in compiler-builtins, so we instead need to get them from libgcc.

Fixes:
https://github.com/rust-lang/rust/issues/46651
https://github.com/rust-lang-nursery/compiler-builtins/issues/201
https://github.com/rust-lang-nursery/compiler-builtins/issues/217

Bump ctest from `482c7f0` to `5c53723`

Bumps [ctest](https://github.com/alexcrichton/ctest) from `482c7f0` to `5c53723`.
<details>
<summary>Commits</summary>

- [`5c53723`](https://github.com/alexcrichton/ctest/commit/5c537236d150da311d67b8ccf4c3c49987b92c8d) Update libc dep
- See full diff in [compare view](https://github.com/alexcrichton/ctest/compare/482c7f0643942174a802d89ad7d460e89b576ed3...5c537236d150da311d67b8ccf4c3c49987b92c8d)
</details>
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Bumps [ctest](https://github.com/alexcrichton/ctest) from `482c7f0` to `5c53723`.
- [Release notes](https://github.com/alexcrichton/ctest/releases)
- [Commits](https://github.com/alexcrichton/ctest/compare/482c7f0643942174a802d89ad7d460e89b576ed3...5c537236d150da311d67b8ccf4c3c49987b92c8d

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Add if_packet.h headers

Some structs for implementing af_packet(7)

Some structs for implementing af_packet(7)

Add linux musl powerpc (32-bit) support

This change adds support for musl on 32-bit powerpc.  Most of the general constants in src/unix/notbsd/linux/musl/b32/mod.rs were different from those of the powerpc port, so I moved them over to the individual architecture-specific submodules.  The same with the ipc_perm structure.

Add ENOATTR for Android

PR based on https://github.com/rust-lang/libc/pull/594

It's defined in Android sysroot so it should work without test workaround (CI should catch it otherwise?).

Remove `#![custom_attribute]`

No longer needed by the looks of it!

No longer needed by the looks of it!

added badges

added Documentation, Latest Version, License badges similar to rand crate. https://crates.io/crates/rand