Make wasm32 buildbot test LLVM backend

configure

@@ -490,6 +490,7 @@ valopt musl-root-armhf "" "arm-unknown-linux-musleabihf install directory"
 valopt musl-root-armv7 "" "armv7-unknown-linux-musleabihf install directory"
 valopt extra-filename "" "Additional data that is hashed and passed to the -C extra-filename flag"
 valopt qemu-armhf-rootfs "" "rootfs in qemu testing, you probably don't want to use this"
+valopt experimental-targets "" "experimental LLVM targets to build"
 
 if [ -e ${CFG_SRC_DIR}.git ]
 then

src/bootstrap/config.rs

@@ -497,6 +497,9 @@ impl Config {
                 "CFG_TARGET" if value.len() > 0 => {
                     self.target.extend(value.split(" ").map(|s| s.to_string()));
                 }
+                "CFG_EXPERIMENTAL_TARGETS" if value.len() > 0 => {
+                    self.llvm_experimental_targets = Some(value.to_string());
+                }
                 "CFG_MUSL_ROOT" if value.len() > 0 => {
                     self.musl_root = Some(parse_configure_path(value));
                 }

src/ci/docker/disabled/wasm32/Dockerfile

@@ -11,16 +11,22 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
   cmake \
   sudo \
   gdb \
-  xz-utils
+  xz-utils \
+  jq \
+  bzip2
 
 # dumb-init
 COPY scripts/dumb-init.sh /scripts/
 RUN sh /scripts/dumb-init.sh
 
 # emscripten
-COPY scripts/emscripten.sh /scripts/
-RUN bash /scripts/emscripten.sh
-COPY wasm32/node.sh /usr/local/bin/node
+COPY scripts/emscripten-wasm.sh /scripts/
+RUN bash /scripts/emscripten-wasm.sh
+COPY disabled/wasm32/node.sh /usr/local/bin/node
+
+# cache
+COPY scripts/sccache.sh /scripts/
+RUN sh /scripts/sccache.sh
 
 # env
 ENV PATH=$PATH:/emsdk-portable
@@ -30,15 +36,11 @@ ENV EMSCRIPTEN=/emsdk-portable/emscripten/1.37.13/
 ENV BINARYEN_ROOT=/emsdk-portable/clang/e1.37.13_64bit/binaryen/
 ENV EM_CONFIG=/emsdk-portable/.emscripten
 
-ENV TARGETS=wasm32-unknown-emscripten
+ENV TARGETS=wasm32-unknown-emscripten,wasm32-experimental-emscripten
 
-ENV RUST_CONFIGURE_ARGS --target=$TARGETS
+ENV RUST_CONFIGURE_ARGS --target=$TARGETS --experimental-targets=WebAssembly
 
 ENV SCRIPT python2.7 ../x.py test --target $TARGETS
 
-# cache
-COPY scripts/sccache.sh /scripts/
-RUN sh /scripts/sccache.sh
-
 # init
 ENTRYPOINT ["/usr/bin/dumb-init", "--"]

src/ci/docker/scripts/emscripten-wasm.sh

@@ -0,0 +1,64 @@
+# 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.
+
+set -ex
+
+hide_output() {
+  set +x
+  on_err="
+echo ERROR: An error was encountered with the build.
+cat /tmp/build.log
+exit 1
+"
+  trap "$on_err" ERR
+  bash -c "while true; do sleep 30; echo \$(date) - building ...; done" &
+  PING_LOOP_PID=$!
+  $@ &> /tmp/build.log
+  trap - ERR
+  kill $PING_LOOP_PID
+  rm -f /tmp/build.log
+  set -x
+}
+
+# Download emsdk
+cd /
+curl -L https://s3.amazonaws.com/mozilla-games/emscripten/releases/emsdk-portable.tar.gz | \
+    tar -xz
+
+# Download last known good emscripten from WebAssembly waterfall
+BUILD=$(curl -L https://storage.googleapis.com/wasm-llvm/builds/linux/lkgr.json | \
+    jq '.build | tonumber')
+curl -L https://storage.googleapis.com/wasm-llvm/builds/linux/$BUILD/wasm-binaries.tbz2 | \
+    hide_output tar xvkj
+
+# node 8 is required to run wasm
+cd /
+curl -L https://nodejs.org/dist/v8.0.0/node-v8.0.0-linux-x64.tar.xz | \
+    tar -xJ
+
+cd /emsdk-portable
+./emsdk update
+hide_output ./emsdk install sdk-1.37.13-64bit
+./emsdk activate sdk-1.37.13-64bit
+
+# Make emscripten use wasm-ready node and LLVM tools
+echo "NODE_JS='/node-v8.0.0-linux-x64/bin/node'" >> /root/.emscripten
+echo "LLVM_ROOT='/wasm-install/bin'" >> /root/.emscripten
+
+# Make emsdk usable by any user
+cp /root/.emscripten /emsdk-portable
+chmod a+rxw -R /emsdk-portable
+
+# Compile and cache libc
+source ./emsdk_env.sh
+echo "main(){}" > a.c
+HOME=/emsdk-portable/ emcc a.c
+HOME=/emsdk-portable/ emcc -s WASM=1 a.c
+rm -f a.*

src/ci/docker/scripts/emscripten.sh

@@ -50,4 +50,4 @@ chmod a+rxw -R /emsdk-portable
 # node 8 is required to run wasm
 cd /
 curl -L https://nodejs.org/dist/v8.0.0/node-v8.0.0-linux-x64.tar.xz | \
-    tar -xJ
+  tar -xJ

src/librustc_back/target/mod.rs

@@ -282,6 +282,9 @@ pub struct TargetOptions {
     /// user-defined libraries.
     pub post_link_args: LinkArgs,
 
+    /// Environment variables to be set before invoking the linker.
+    pub link_env: Vec<(String, String)>,
+
     /// Extra arguments to pass to the external assembler (when used)
     pub asm_args: Vec<String>,
 
@@ -451,6 +454,7 @@ impl Default for TargetOptions {
             pre_link_objects_dll: Vec::new(),
             post_link_objects: Vec::new(),
             late_link_args: LinkArgs::new(),
+            link_env: Vec::new(),
             archive_format: "gnu".to_string(),
             custom_unwind_resume: false,
             lib_allocation_crate: "alloc_system".to_string(),
@@ -620,6 +624,21 @@ impl Target {
                     base.options.$key_name = args;
                 }
             } );
+            ($key_name:ident, env) => ( {
+                let name = (stringify!($key_name)).replace("_", "-");
+                if let Some(a) = obj.find(&name[..]).and_then(|o| o.as_array()) {
+                    for o in a {
+                        if let Some(s) = o.as_string() {
+                            let p = s.split('=').collect::<Vec<_>>();
+                            if p.len() == 2 {
+                                let k = p[0].to_string();
+                                let v = p[1].to_string();
+                                base.options.$key_name.push((k, v));
+                            }
+                        }
+                    }
+                }
+            } );
         }
 
         key!(is_builtin, bool);
@@ -631,6 +650,7 @@ impl Target {
         key!(late_link_args, link_args);
         key!(post_link_objects, list);
         key!(post_link_args, link_args);
+        key!(link_env, env);
         key!(asm_args, list);
         key!(cpu);
         key!(features);
@@ -785,6 +805,17 @@ impl ToJson for Target {
                     d.insert(name.to_string(), obj.to_json());
                 }
             } );
+            (env - $attr:ident) => ( {
+                let name = (stringify!($attr)).replace("_", "-");
+                if default.$attr != self.options.$attr {
+                    let obj = self.options.$attr
+                        .iter()
+                        .map(|&(ref k, ref v)| k.clone() + "=" + &v)
+                        .collect::<Vec<_>>();
+                    d.insert(name.to_string(), obj.to_json());
+                }
+            } );
+
         }
 
         target_val!(llvm_target);
@@ -806,6 +837,7 @@ impl ToJson for Target {
         target_option_val!(link_args - late_link_args);
         target_option_val!(post_link_objects);
         target_option_val!(link_args - post_link_args);
+        target_option_val!(env - link_env);
         target_option_val!(asm_args);
         target_option_val!(cpu);
         target_option_val!(features);

src/librustc_back/target/wasm32_experimental_emscripten.rs

@@ -30,6 +30,7 @@ pub fn target() -> Result<Target, String> {
         // possibly interpret the wasm, and a .wasm file
         exe_suffix: ".js".to_string(),
         linker_is_gnu: true,
+        link_env: vec![("EMCC_WASM_BACKEND".to_string(), "1".to_string())],
         allow_asm: false,
         obj_is_bitcode: true,
         is_like_emscripten: true,

src/librustc_trans/back/link.rs

@@ -785,6 +785,9 @@ fn link_natively(sess: &Session,
     if let Some(args) = sess.target.target.options.post_link_args.get(&flavor) {
         cmd.args(args);
     }
+    for &(ref k, ref v) in &sess.target.target.options.link_env {
+        cmd.env(k, v);
+    }
 
     if sess.opts.debugging_opts.print_link_args {
         println!("{:?}", &cmd);

src/tools/compiletest/src/runtest.rs

@@ -1338,7 +1338,6 @@ actual:\n\
                              input)
     }
 
-
     fn compose_and_run(&self,
                        ProcArgs{ args, prog }: ProcArgs,
                        procenv: Vec<(String, String)> ,