Auto merge of #45224 - malbarbo:x32, r=alexcrichton

Add x86_64-unknown-linux-gnux32 target

This adds X32 ABI support for Linux on X86_64. Let's package and dist it so we can star testing libc, libstd, etc.

Fixes rust-lang/rfcs#1339

Author: bors

src/Cargo.lock

@@ -34,7 +34,7 @@ cmake = "0.1.23"
 filetime = "0.1"
 num_cpus = "1.0"
 getopts = "0.2"
-cc = "1.0"
+cc = "1.0.1"
 libc = "0.2"
 serde = "1.0.8"
 serde_derive = "1.0.8"

src/bootstrap/Cargo.toml

@@ -5,6 +5,7 @@ RUN sh /scripts/cross-apt-packages.sh
 
 RUN apt-get build-dep -y clang llvm && apt-get install -y --no-install-recommends \
   build-essential \
+  gcc-multilib \
   libedit-dev \
   libgmp-dev \
   libisl-dev \
@@ -47,6 +48,7 @@ ENV TARGETS=x86_64-unknown-fuchsia
 ENV TARGETS=$TARGETS,aarch64-unknown-fuchsia
 ENV TARGETS=$TARGETS,sparcv9-sun-solaris
 ENV TARGETS=$TARGETS,x86_64-sun-solaris
+ENV TARGETS=$TARGETS,x86_64-unknown-linux-gnux32
 
 ENV RUST_CONFIGURE_ARGS --target=$TARGETS --enable-extended
 ENV SCRIPT python2.7 ../x.py dist --target $TARGETS

src/ci/docker/cross2/Dockerfile

@@ -19,7 +19,7 @@ libc = { path = "../rustc/libc_shim" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-cc = "1.0"
+cc = "1.0.1"
 
 [features]
 debug = []

src/liballoc_jemalloc/Cargo.toml

@@ -15,4 +15,4 @@ doc = false
 core = { path = "../libcore" }
 
 [build-dependencies]
-cc = "1.0"
+cc = "1.0.1"

src/libprofiler_builtins/Cargo.toml

@@ -135,6 +135,7 @@ macro_rules! supported_targets {
 
 supported_targets! {
     ("x86_64-unknown-linux-gnu", x86_64_unknown_linux_gnu),
+    ("x86_64-unknown-linux-gnux32", x86_64_unknown_linux_gnux32),
     ("i686-unknown-linux-gnu", i686_unknown_linux_gnu),
     ("i586-unknown-linux-gnu", i586_unknown_linux_gnu),
     ("mips-unknown-linux-gnu", mips_unknown_linux_gnu),

src/librustc_back/target/mod.rs

@@ -0,0 +1,35 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+use LinkerFlavor;
+use target::{Target, TargetResult};
+
+pub fn target() -> TargetResult {
+    let mut base = super::linux_base::opts();
+    base.cpu = "x86-64".to_string();
+    base.max_atomic_width = Some(64);
+    base.pre_link_args.get_mut(&LinkerFlavor::Gcc).unwrap().push("-mx32".to_string());
+    base.stack_probes = true;
+    base.has_elf_tls = false;
+
+    Ok(Target {
+        llvm_target: "x86_64-unknown-linux-gnux32".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        target_c_int_width: "32".to_string(),
+        data_layout: "e-m:e-p:32:32-i64:64-f80:128-n8:16:32:64-S128".to_string(),
+        arch: "x86_64".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "gnu".to_string(),
+        target_vendor: "unknown".to_string(),
+        linker_flavor: LinkerFlavor::Gcc,
+        options: base,
+    })
+}

src/librustc_back/target/x86_64_unknown_linux_gnux32.rs

@@ -18,4 +18,4 @@ rustc_cratesio_shim = { path = "../librustc_cratesio_shim" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-cc = "1.0"
+cc = "1.0.1"

src/librustc_llvm/Cargo.toml

@@ -32,4 +32,4 @@ syntax = { path = "../libsyntax" }
 syntax_pos = { path = "../libsyntax_pos" }
 
 [target."cfg(windows)".dependencies]
-cc = "1.0"
+cc = "1.0.1"

src/librustc_trans/Cargo.toml

@@ -18,4 +18,4 @@ html-diff = "0.0.4"
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-cc = "1.0"
+cc = "1.0.1"

src/librustdoc/Cargo.toml

@@ -36,7 +36,7 @@ rustc_tsan = { path = "../librustc_tsan" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-cc = "1.0"
+cc = "1.0.1"
 
 [features]
 backtrace = []

src/libstd/Cargo.toml

@@ -30,7 +30,7 @@ doctest = false
 core = { path = "../../libcore" }
 
 [build-dependencies]
-cc = "1.0"
+cc = "1.0.1"
 
 [features]
 c = []

src/rustc/compiler_builtins_shim/Cargo.toml

@@ -95,6 +95,7 @@ static TARGETS: &'static [&'static str] = &[
     "x86_64-unknown-freebsd",
     "x86_64-unknown-fuchsia",
     "x86_64-unknown-linux-gnu",
+    "x86_64-unknown-linux-gnux32",
     "x86_64-unknown-linux-musl",
     "x86_64-unknown-netbsd",
     "x86_64-unknown-redox",