Remove librustuv

This commit removes the `librustuv` crate.

See the [runtime removal
RFC](rust-lang/rfcs#230) for more context.

See [green-rs](https://github.com/alexcrichton/green-rs/) for a possible
migration path if you wish to continue using green-threaded I/O. The
library provides its own I/O API surface.

[breaking-change]

Author: aturon

mk/crates.mk

@@ -49,7 +49,7 @@
 # automatically generated for all stage/host/target combinations.
 ################################################################################
 
-TARGET_CRATES := libc std green rustuv native flate arena glob term semver \
+TARGET_CRATES := libc std green native flate arena glob term semver \
                  uuid serialize sync getopts collections num test time rand \
                  url log regex graphviz core rbml rlibc alloc debug rustrt \
                  unicode
@@ -69,7 +69,6 @@ DEPS_std := core libc rand alloc collections rustrt sync unicode \
 	native:rust_builtin native:backtrace
 DEPS_graphviz := std
 DEPS_green := std native:context_switch
-DEPS_rustuv := std native:uv native:uv_support
 DEPS_native := std
 DEPS_syntax := std term serialize log fmt_macros debug arena libc
 DEPS_rustc := syntax flate arena serialize getopts rbml \
@@ -102,7 +101,7 @@ DEPS_regex := std
 DEPS_regex_macros = rustc syntax std regex
 DEPS_fmt_macros = std
 
-TOOL_DEPS_compiletest := test green rustuv getopts
+TOOL_DEPS_compiletest := test getopts
 TOOL_DEPS_rustdoc := rustdoc native
 TOOL_DEPS_rustc := rustc native
 TOOL_SOURCE_compiletest := $(S)src/compiletest/compiletest.rs

src/README.md

@@ -57,8 +57,6 @@ Source layout:
 | `test/auxiliary`    | - Dependencies of tests                                   |
 | ------------------- | --------------------------------------------------------- |
 | `librustdoc/`       | The Rust API documentation tool                           |
-| `libuv/`            | The libuv submodule                                       |
-| `librustuv/`        | Rust libuv support code                                   |
 | ------------------- | --------------------------------------------------------- |
 | `llvm/`             | The LLVM submodule                                        |
 | `rustllvm/`         | LLVM support code                                         |