Add a wasi target

Author: alexcrichton

Cargo.lock

@@ -68,5 +68,8 @@ rustc-workspace-hack = { path = 'src/tools/rustc-workspace-hack' }
 # here
 rustc-std-workspace-core = { path = 'src/tools/rustc-std-workspace-core' }
 
+libc = { git = 'https://github.com/alexcrichton/libc', branch = 'wasi' }
+compiler_builtins = { git = 'https://github.com/alexcrichton/compiler-builtins', branch = 'wasi' }
+
 [patch."https://github.com/rust-lang/rust-clippy"]
 clippy_lints = { path = "src/tools/clippy/clippy_lints" }

Cargo.toml

@@ -478,6 +478,9 @@
 # linked binaries
 #musl-root = "..."
 
+# The root location of the `wasm32-unknown-wasi` sysroot.
+#wasi-root = "..."
+
 # Used in testing for configuring where the QEMU images are located, you
 # probably don't want to use this.
 #qemu-rootfs = "..."

config.toml.example

@@ -116,8 +116,8 @@ fn main() {
             cmd.arg("-Cprefer-dynamic");
         }
 
-        // Help the libc crate compile by assisting it in finding the MUSL
-        // native libraries.
+        // Help the libc crate compile by assisting it in finding various
+        // sysroot native libraries.
         if let Some(s) = env::var_os("MUSL_ROOT") {
             if target.contains("musl") {
                 let mut root = OsString::from("native=");
@@ -126,6 +126,12 @@ fn main() {
                 cmd.arg("-L").arg(&root);
             }
         }
+        if let Some(s) = env::var_os("WASI_ROOT") {
+            let mut root = OsString::from("native=");
+            root.push(&s);
+            root.push("/lib/wasm32-wasi");
+            cmd.arg("-L").arg(&root);
+        }
 
         // Override linker if necessary.
         if let Ok(target_linker) = env::var("RUSTC_TARGET_LINKER") {

src/bootstrap/bin/rustc.rs

@@ -127,6 +127,13 @@ fn copy_third_party_objects(builder: &Builder<'_>, compiler: &Compiler, target:
                 &libdir.join(obj),
             );
         }
+    } else if target.contains("-wasi") {
+        for &obj in &["crt1.o"] {
+            builder.copy(
+                &builder.wasi_root(target).unwrap().join("lib/wasm32-wasi").join(obj),
+                &libdir.join(obj),
+            );
+        }
     }
 
     // Copies libunwind.a compiled to be linked wit x86_64-fortanix-unknown-sgx.
@@ -188,6 +195,12 @@ pub fn std_cargo(builder: &Builder<'_>,
                 cargo.env("MUSL_ROOT", p);
             }
         }
+
+        if target.contains("-wasi") {
+            if let Some(p) = builder.wasi_root(target) {
+                cargo.env("WASI_ROOT", p);
+            }
+        }
     }
 }
 

src/bootstrap/compile.rs

@@ -170,6 +170,7 @@ pub struct Target {
     pub ndk: Option<PathBuf>,
     pub crt_static: Option<bool>,
     pub musl_root: Option<PathBuf>,
+    pub wasi_root: Option<PathBuf>,
     pub qemu_rootfs: Option<PathBuf>,
     pub no_std: bool,
 }
@@ -346,6 +347,7 @@ struct TomlTarget {
     android_ndk: Option<String>,
     crt_static: Option<bool>,
     musl_root: Option<String>,
+    wasi_root: Option<String>,
     qemu_rootfs: Option<String>,
 }
 
@@ -609,6 +611,7 @@ impl Config {
                 target.linker = cfg.linker.clone().map(PathBuf::from);
                 target.crt_static = cfg.crt_static.clone();
                 target.musl_root = cfg.musl_root.clone().map(PathBuf::from);
+                target.wasi_root = cfg.wasi_root.clone().map(PathBuf::from);
                 target.qemu_rootfs = cfg.qemu_rootfs.clone().map(PathBuf::from);
 
                 config.target_config.insert(INTERNER.intern_string(triple.clone()), target);

src/bootstrap/config.rs

@@ -843,6 +843,13 @@ impl Build {
             .map(|p| &**p)
     }
 
+    /// Returns the sysroot for the wasi target, if defined
+    fn wasi_root(&self, target: Interned<String>) -> Option<&Path> {
+        self.config.target_config.get(&target)
+            .and_then(|t| t.wasi_root.as_ref())
+            .map(|p| &**p)
+    }
+
     /// Returns `true` if this is a no-std `target`, if defined
     fn no_std(&self, target: Interned<String>) -> Option<bool> {
         self.config.target_config.get(&target)

src/bootstrap/lib.rs

@@ -34,6 +34,11 @@ COPY dist-various-2/build-x86_64-fortanix-unknown-sgx-toolchain.sh /tmp/
 # Any update to the commit id here, should cause the container image to be re-built from this point on.
 RUN /tmp/build-x86_64-fortanix-unknown-sgx-toolchain.sh "53b586346f2c7870e20b170decdc30729d97c42b"
 
+COPY dist-various-2/build-wasi-toolchain.sh /tmp/
+# FIXME: remove this line and uncomment the git clone
+COPY dist-various-2/reference-sysroot-wasi/ /tmp/wut/
+RUN /tmp/build-wasi-toolchain.sh
+
 COPY scripts/sccache.sh /scripts/
 RUN sh /scripts/sccache.sh
 
@@ -66,6 +71,7 @@ ENV TARGETS=x86_64-fuchsia
 ENV TARGETS=$TARGETS,aarch64-fuchsia
 ENV TARGETS=$TARGETS,sparcv9-sun-solaris
 ENV TARGETS=$TARGETS,wasm32-unknown-unknown
+ENV TARGETS=$TARGETS,wasm32-unknown-wasi
 ENV TARGETS=$TARGETS,x86_64-sun-solaris
 ENV TARGETS=$TARGETS,x86_64-unknown-linux-gnux32
 ENV TARGETS=$TARGETS,x86_64-unknown-cloudabi
@@ -74,5 +80,6 @@ ENV TARGETS=$TARGETS,nvptx64-nvidia-cuda
 
 ENV X86_FORTANIX_SGX_LIBS="/x86_64-fortanix-unknown-sgx/lib/"
 
-ENV RUST_CONFIGURE_ARGS --enable-extended --enable-lld --disable-docs
+ENV RUST_CONFIGURE_ARGS --enable-extended --enable-lld --disable-docs \
+  --set target.wasm32-unknown-wasi.wasi-root=/wasm32-unknown-wasi
 ENV SCRIPT python2.7 ../x.py dist --target $TARGETS

src/ci/docker/dist-various-2/Dockerfile

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+set -ex
+
+curl https://prereleases.llvm.org/8.0.0/rc3/clang+llvm-8.0.0-rc3-x86_64-linux-gnu-ubuntu-14.04.tar.xz | \
+  tar xJf -
+export PATH=`pwd`/clang+llvm-8.0.0-rc3-x86_64-linux-gnu-ubuntu-14.04/bin:$PATH
+
+# FIXME: uncomment this line and remove the next
+#git clone https://github.com/cranestation/reference-sysroot-wasi
+git clone /tmp/wut reference-sysroot-wasi
+
+cd reference-sysroot-wasi
+git reset --hard d0d8bc47946948646cb50a37471d9516c90d9786
+make -j$(nproc) INSTALL_DIR=/wasm32-unknown-wasi
+make install INSTALL_DIR=/wasm32-unknown-wasi
+
+cd ..
+rm -rf reference-sysroot-wasi
+rm -rf clang+llvm*

src/ci/docker/dist-various-2/build-wasi-toolchain.sh

@@ -0,0 +1 @@
+Subproject commit d0d8bc47946948646cb50a37471d9516c90d9786