Add x86_64-unknown-linux-gnux32 target

Author: malbarbo

src/librustc_back/target/mod.rs

@@ -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/x86_64_unknown_linux_gnux32.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,
+    })
+}