Auto merge of #35060 - japaric:arm-musl, r=alexcrichton

Add ARM MUSL targets

Rebase of #33189.

I tested this by producing a std for `arm-unknown-linux-musleabi` then I cross compiled Hello world to said target. Checked that the produced binary was statically linked and verified that the binary worked under QEMU.

This depends on rust-lang/libc#341. I'll have to update this PR after that libc PR is merged.

I'm also working on generating ARM musl cross toolchain via crosstool-ng. Once I verified those work, I'll send a PR to rust-buildbot.

r? @alexcrichton
cc @timonvo

20 files changed, 143 insertions, 20 deletions

diff --git a/configure b/configure
index d2ec457a1c8..a7e24a506fb 100755
--- a/configure
+++ b/configure
@@ -1192,7 +1192,7 @@ do
             ;;
 
 
-        x86_64-*-musl)
+        x86_64-*-musl | arm-*-musleabi)
             if [ ! -f $CFG_MUSL_ROOT/lib/libc.a ]
             then
                 err "musl libc $CFG_MUSL_ROOT/lib/libc.a not found"
diff --git a/mk/cfg/arm-unknown-linux-musleabi.mk b/mk/cfg/arm-unknown-linux-musleabi.mk
new file mode 100644
index 00000000000..8120250150d
--- /dev/null
+++ b/mk/cfg/arm-unknown-linux-musleabi.mk
@@ -0,0 +1,3 @@
+# This file is intentially left empty to indicate that, while this target is
+# supported, it's not supported using plain GNU Make builds. Use a --rustbuild
+# instead.
\ No newline at end of file
diff --git a/mk/cfg/arm-unknown-linux-musleabihf.mk b/mk/cfg/arm-unknown-linux-musleabihf.mk
new file mode 100644
index 00000000000..8120250150d
--- /dev/null
+++ b/mk/cfg/arm-unknown-linux-musleabihf.mk
@@ -0,0 +1,3 @@
+# This file is intentially left empty to indicate that, while this target is
+# supported, it's not supported using plain GNU Make builds. Use a --rustbuild
+# instead.
\ No newline at end of file
diff --git a/mk/cfg/armv7-unknown-linux-musleabihf.mk b/mk/cfg/armv7-unknown-linux-musleabihf.mk
new file mode 100644
index 00000000000..8120250150d
--- /dev/null
+++ b/mk/cfg/armv7-unknown-linux-musleabihf.mk
@@ -0,0 +1,3 @@
+# This file is intentially left empty to indicate that, while this target is
+# supported, it's not supported using plain GNU Make builds. Use a --rustbuild
+# instead.
\ No newline at end of file
diff --git a/src/bootstrap/Cargo.lock b/src/bootstrap/Cargo.lock
index 1290f2a404b..02698d6f7a1 100644
--- a/src/bootstrap/Cargo.lock
+++ b/src/bootstrap/Cargo.lock
@@ -7,8 +7,8 @@ dependencies = [
  "filetime 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "gcc 0.3.31 (git+https://github.com/alexcrichton/gcc-rs)",
  "getopts 0.2.14 (registry+https://github.com/rust-lang/crates.io-index)",
- "kernel32-sys 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "libc 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
  "md5 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -33,7 +33,7 @@ name = "filetime"
 version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -53,7 +53,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
 name = "kernel32-sys"
-version = "0.2.1"
+version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
  "winapi 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -62,7 +62,7 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.9"
+version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -75,7 +75,7 @@ name = "num_cpus"
 version = "0.2.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 dependencies = [
- "libc 0.2.9 (registry+https://github.com/rust-lang/crates.io-index)",
+ "libc 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs
index 8ec9c7f0109..061192ebd13 100644
--- a/src/bootstrap/compile.rs
+++ b/src/bootstrap/compile.rs
@@ -92,8 +92,7 @@ pub fn std_link(build: &Build,
     }
     add_to_sysroot(&out_dir, &libdir);
 
-    if target.contains("musl") &&
-       (target.contains("x86_64") || target.contains("i686")) {
+    if target.contains("musl") && !target.contains("mips") {
         copy_third_party_objects(build, target, &libdir);
     }
 }
diff --git a/src/bootstrap/sanity.rs b/src/bootstrap/sanity.rs
index 73749246758..09f96782e71 100644
--- a/src/bootstrap/sanity.rs
+++ b/src/bootstrap/sanity.rs
@@ -109,7 +109,7 @@ pub fn check(build: &mut Build) {
         }
 
         // Make sure musl-root is valid if specified
-        if target.contains("musl") && (target.contains("x86_64") || target.contains("i686")) {
+        if target.contains("musl") && !target.contains("mips") {
             match build.config.musl_root {
                 Some(ref root) => {
                     if fs::metadata(root.join("lib/libc.a")).is_err() {
diff --git a/src/liballoc_jemalloc/Cargo.toml b/src/liballoc_jemalloc/Cargo.toml
index 768a0c2c0a5..25b3c8a3a0a 100644
--- a/src/liballoc_jemalloc/Cargo.toml
+++ b/src/liballoc_jemalloc/Cargo.toml
@@ -16,7 +16,7 @@ libc = { path = "../rustc/libc_shim" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-gcc = "0.3.17"
+gcc = "0.3.27"
 
 [features]
 debug = []
diff --git a/src/liballoc_jemalloc/build.rs b/src/liballoc_jemalloc/build.rs
index d1b3583d256..dc1b8d6ea98 100644
--- a/src/liballoc_jemalloc/build.rs
+++ b/src/liballoc_jemalloc/build.rs
@@ -73,7 +73,16 @@ fn main() {
                    .replace("\\", "/"))
        .current_dir(&build_dir)
        .env("CC", compiler.path())
-       .env("EXTRA_CFLAGS", cflags)
+       .env("EXTRA_CFLAGS", cflags.clone())
+       // jemalloc generates Makefile deps using GCC's "-MM" flag. This means
+       // that GCC will run the preprocessor, and only the preprocessor, over
+       // jemalloc's source files. If we don't specify CPPFLAGS, then at least
+       // on ARM that step fails with a "Missing implementation for 32-bit
+       // atomic operations" error. This is because no "-march" flag will be
+       // passed to GCC, and then GCC won't define the
+       // "__GCC_HAVE_SYNC_COMPARE_AND_SWAP_4" macro that jemalloc needs to
+       // select an atomic operation implementation.
+       .env("CPPFLAGS", cflags.clone())
        .env("AR", &ar)
        .env("RANLIB", format!("{} s", ar.display()));
 
diff --git a/src/libflate/Cargo.toml b/src/libflate/Cargo.toml
index 52aa6bb86ef..5423da9c81c 100644
--- a/src/libflate/Cargo.toml
+++ b/src/libflate/Cargo.toml
@@ -11,4 +11,4 @@ crate-type = ["dylib"]
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-gcc = "0.3"
+gcc = "0.3.27"
diff --git a/src/liblibc b/src/liblibc
-Subproject b0d62534d48b711c8978d1bbe8cca0558ae7b1c
+Subproject 5066b7dcab7e700844b0e2ba71b8af9dc627a59
diff --git a/src/librustc_back/target/arm_unknown_linux_musleabi.rs b/src/librustc_back/target/arm_unknown_linux_musleabi.rs
new file mode 100644
index 00000000000..028c91eadae
--- /dev/null
+++ b/src/librustc_back/target/arm_unknown_linux_musleabi.rs
@@ -0,0 +1,34 @@
+// Copyright 2016 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 target::{Target, TargetResult};
+
+pub fn target() -> TargetResult {
+    let mut base = super::linux_musl_base::opts();
+
+    // Most of these settings are copied from the arm_unknown_linux_gnueabi
+    // target.
+    base.features = "+v6".to_string();
+    base.max_atomic_width = 64;
+    Ok(Target {
+        // It's important we use "gnueabi" and not "musleabi" here. LLVM uses it
+        // to determine the calling convention and float ABI, and it doesn't
+        // support the "musleabi" value.
+        llvm_target: "arm-unknown-linux-gnueabi".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        data_layout: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
+        arch: "arm".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "musl".to_string(),
+        target_vendor: "unknown".to_string(),
+        options: base,
+    })
+}
diff --git a/src/librustc_back/target/arm_unknown_linux_musleabihf.rs b/src/librustc_back/target/arm_unknown_linux_musleabihf.rs
new file mode 100644
index 00000000000..c7dda186f42
--- /dev/null
+++ b/src/librustc_back/target/arm_unknown_linux_musleabihf.rs
@@ -0,0 +1,34 @@
+// Copyright 2016 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 target::{Target, TargetResult};
+
+pub fn target() -> TargetResult {
+    let mut base = super::linux_musl_base::opts();
+
+    // Most of these settings are copied from the arm_unknown_linux_gnueabihf
+    // target.
+    base.features = "+v6,+vfp2".to_string();
+    base.max_atomic_width = 64;
+    Ok(Target {
+        // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
+        // uses it to determine the calling convention and float ABI, and it
+        // doesn't support the "musleabihf" value.
+        llvm_target: "arm-unknown-linux-gnueabihf".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        data_layout: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
+        arch: "arm".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "musl".to_string(),
+        target_vendor: "unknown".to_string(),
+        options: base,
+    })
+}
diff --git a/src/librustc_back/target/armv7_unknown_linux_musleabihf.rs b/src/librustc_back/target/armv7_unknown_linux_musleabihf.rs
new file mode 100644
index 00000000000..e40704e5d49
--- /dev/null
+++ b/src/librustc_back/target/armv7_unknown_linux_musleabihf.rs
@@ -0,0 +1,35 @@
+// Copyright 2016 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 target::{Target, TargetResult};
+
+pub fn target() -> TargetResult {
+    let mut base = super::linux_musl_base::opts();
+
+    // Most of these settings are copied from the armv7_unknown_linux_gnueabihf
+    // target.
+    base.features = "+v7,+vfp3,+neon".to_string();
+    base.cpu = "cortex-a8".to_string();
+    base.max_atomic_width = 64;
+    Ok(Target {
+        // It's important we use "gnueabihf" and not "musleabihf" here. LLVM
+        // uses it to determine the calling convention and float ABI, and LLVM
+        // doesn't support the "musleabihf" value.
+        llvm_target: "armv7-unknown-linux-gnueabihf".to_string(),
+        target_endian: "little".to_string(),
+        target_pointer_width: "32".to_string(),
+        data_layout: "e-m:e-p:32:32-i64:64-v128:64:128-a:0:32-n32-S64".to_string(),
+        arch: "arm".to_string(),
+        target_os: "linux".to_string(),
+        target_env: "musl".to_string(),
+        target_vendor: "unknown".to_string(),
+        options: base,
+    })
+}
diff --git a/src/librustc_back/target/mod.rs b/src/librustc_back/target/mod.rs
index f5314809228..ecfbeaca351 100644
--- a/src/librustc_back/target/mod.rs
+++ b/src/librustc_back/target/mod.rs
@@ -134,7 +134,10 @@ supported_targets! {
     ("powerpc64le-unknown-linux-gnu", powerpc64le_unknown_linux_gnu),
     ("arm-unknown-linux-gnueabi", arm_unknown_linux_gnueabi),
     ("arm-unknown-linux-gnueabihf", arm_unknown_linux_gnueabihf),
+    ("arm-unknown-linux-musleabi", arm_unknown_linux_musleabi),
+    ("arm-unknown-linux-musleabihf", arm_unknown_linux_musleabihf),
     ("armv7-unknown-linux-gnueabihf", armv7_unknown_linux_gnueabihf),
+    ("armv7-unknown-linux-musleabihf", armv7_unknown_linux_musleabihf),
     ("aarch64-unknown-linux-gnu", aarch64_unknown_linux_gnu),
     ("x86_64-unknown-linux-musl", x86_64_unknown_linux_musl),
     ("i686-unknown-linux-musl", i686_unknown_linux_musl),
diff --git a/src/librustc_llvm/Cargo.toml b/src/librustc_llvm/Cargo.toml
index 05d20911a5d..f97daa22ff6 100644
--- a/src/librustc_llvm/Cargo.toml
+++ b/src/librustc_llvm/Cargo.toml
@@ -17,4 +17,4 @@ rustc_bitflags = { path = "../librustc_bitflags" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-gcc = "0.3"
+gcc = "0.3.27"
diff --git a/src/librustdoc/Cargo.toml b/src/librustdoc/Cargo.toml
index a41d3b0253a..3e510bdc900 100644
--- a/src/librustdoc/Cargo.toml
+++ b/src/librustdoc/Cargo.toml
@@ -28,4 +28,4 @@ log = { path = "../liblog" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-gcc = "0.3"
+gcc = "0.3.27"
diff --git a/src/libstd/Cargo.toml b/src/libstd/Cargo.toml
index b442d21b72b..3ce6841fdd4 100644
--- a/src/libstd/Cargo.toml
+++ b/src/libstd/Cargo.toml
@@ -24,7 +24,7 @@ unwind = { path = "../libunwind" }
 
 [build-dependencies]
 build_helper = { path = "../build_helper" }
-gcc = "0.3"
+gcc = "0.3.27"
 
 [features]
 backtrace = []
diff --git a/src/libunwind/build.rs b/src/libunwind/build.rs
index ebe6fd54799..fd446f5a4f9 100644
--- a/src/libunwind/build.rs
+++ b/src/libunwind/build.rs
@@ -16,7 +16,7 @@ fn main() {
     let target = env::var("TARGET").unwrap();
 
     if target.contains("linux") {
-        if target.contains("musl") && (target.contains("x86_64") || target.contains("i686")) {
+        if target.contains("musl") && !target.contains("mips") {
             println!("cargo:rustc-link-lib=static=unwind");
         } else if !target.contains("android") {
             println!("cargo:rustc-link-lib=gcc_s");
diff --git a/src/rustc/std_shim/Cargo.lock b/src/rustc/std_shim/Cargo.lock
index bad46966ffa..70aef55d799 100644
--- a/src/rustc/std_shim/Cargo.lock
+++ b/src/rustc/std_shim/Cargo.lock
@@ -18,7 +18,7 @@ version = "0.0.0"
 dependencies = [
  "build_helper 0.1.0",
  "core 0.0.0",
- "gcc 0.3.26 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.0.0",
 ]
 
@@ -49,7 +49,7 @@ version = "0.0.0"
 
 [[package]]
 name = "gcc"
-version = "0.3.26"
+version = "0.3.27"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
@@ -101,7 +101,7 @@ dependencies = [
  "build_helper 0.1.0",
  "collections 0.0.0",
  "core 0.0.0",
- "gcc 0.3.26 (registry+https://github.com/rust-lang/crates.io-index)",
+ "gcc 0.3.27 (registry+https://github.com/rust-lang/crates.io-index)",
  "libc 0.0.0",
  "panic_abort 0.0.0",
  "panic_unwind 0.0.0",