Merge pull request #1187 from bjorn3/feature_gating

Preparations for building as part of rustc

7 files changed, 23 insertions, 11 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 2e34717f419..02098b135f7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -37,7 +37,8 @@ smallvec = "1.6.1"
 #gimli = { path = "../" }
 
 [features]
-default = ["jit", "inline_asm"]
+# Enable features not ready to be enabled when compiling as part of rustc
+unstable-features = ["jit", "inline_asm"]
 jit = ["cranelift-jit", "libloading"]
 inline_asm = []
 
diff --git a/build_system/build_backend.rs b/build_system/build_backend.rs
index 1df2bcc4541..150b6d01a6b 100644
--- a/build_system/build_backend.rs
+++ b/build_system/build_backend.rs
@@ -4,7 +4,7 @@ use std::process::Command;
 
 pub(crate) fn build_backend(channel: &str, host_triple: &str) -> PathBuf {
     let mut cmd = Command::new("cargo");
-    cmd.arg("build").arg("--target").arg(host_triple);
+    cmd.arg("build").arg("--target").arg(host_triple).arg("--features").arg("unstable-features");
 
     match channel {
         "debug" => {}
diff --git a/docs/usage.md b/docs/usage.md
index 956d5905a97..87eec0e818b 100644
--- a/docs/usage.md
+++ b/docs/usage.md
@@ -36,7 +36,7 @@ $ $cg_clif_dir/build/cargo jit
 or
 
 ```bash
-$ $cg_clif_dir/build/bin/cg_clif -Cllvm-args=mode=jit -Cprefer-dynamic my_crate.rs
+$ $cg_clif_dir/build/bin/cg_clif -Zunstable-features -Cllvm-args=mode=jit -Cprefer-dynamic my_crate.rs
 ```
 
 There is also an experimental lazy jit mode. In this mode functions are only compiled once they are
@@ -52,7 +52,7 @@ These are a few functions that allow you to easily run rust code from the shell
 
 ```bash
 function jit_naked() {
-    echo "$@" | $cg_clif_dir/build/bin/cg_clif - -Cllvm-args=mode=jit -Cprefer-dynamic
+    echo "$@" | $cg_clif_dir/build/bin/cg_clif - -Zunstable-features -Cllvm-args=mode=jit -Cprefer-dynamic
 }
 
 function jit() {
diff --git a/scripts/cargo.rs b/scripts/cargo.rs
index b7e8dd44974..89ec8da77d3 100644
--- a/scripts/cargo.rs
+++ b/scripts/cargo.rs
@@ -44,7 +44,11 @@ fn main() {
             );
             std::array::IntoIter::new(["rustc".to_string()])
                 .chain(env::args().skip(2))
-                .chain(["--".to_string(), "-Cllvm-args=mode=jit".to_string()])
+                .chain([
+                    "--".to_string(),
+                    "-Zunstable-features".to_string(),
+                    "-Cllvm-args=mode=jit".to_string(),
+                ])
                 .collect()
         }
         Some("lazy-jit") => {
@@ -54,7 +58,11 @@ fn main() {
             );
             std::array::IntoIter::new(["rustc".to_string()])
                 .chain(env::args().skip(2))
-                .chain(["--".to_string(), "-Cllvm-args=mode=jit-lazy".to_string()])
+                .chain([
+                    "--".to_string(),
+                    "-Zunstable-features".to_string(),
+                    "-Cllvm-args=mode=jit-lazy".to_string(),
+                ])
                 .collect()
         }
         _ => env::args().skip(1).collect(),
diff --git a/scripts/filter_profile.rs b/scripts/filter_profile.rs
index 9e196afbe4f..c4801a0a87b 100755
--- a/scripts/filter_profile.rs
+++ b/scripts/filter_profile.rs
@@ -5,7 +5,7 @@ pushd $(dirname "$0")/../
 source scripts/config.sh
 RUSTC="$(pwd)/build/bin/cg_clif"
 popd
-PROFILE=$1 OUTPUT=$2 exec $RUSTC -Cllvm-args=mode=jit -Cprefer-dynamic $0
+PROFILE=$1 OUTPUT=$2 exec $RUSTC -Zunstable-options -Cllvm-args=mode=jit -Cprefer-dynamic $0
 #*/
 
 //! This program filters away uninteresting samples and trims uninteresting frames for stackcollapse
diff --git a/scripts/tests.sh b/scripts/tests.sh
index 5df04c533a7..08c07dfad42 100755
--- a/scripts/tests.sh
+++ b/scripts/tests.sh
@@ -16,10 +16,10 @@ function no_sysroot_tests() {
 
     if [[ "$JIT_SUPPORTED" = "1" ]]; then
         echo "[JIT] mini_core_hello_world"
-        CG_CLIF_JIT_ARGS="abc bcd" $MY_RUSTC -Cllvm-args=mode=jit -Cprefer-dynamic example/mini_core_hello_world.rs --cfg jit --target "$HOST_TRIPLE"
+        CG_CLIF_JIT_ARGS="abc bcd" $MY_RUSTC -Zunstable-options -Cllvm-args=mode=jit -Cprefer-dynamic example/mini_core_hello_world.rs --cfg jit --target "$HOST_TRIPLE"
 
         echo "[JIT-lazy] mini_core_hello_world"
-        CG_CLIF_JIT_ARGS="abc bcd" $MY_RUSTC -Cllvm-args=mode=jit-lazy -Cprefer-dynamic example/mini_core_hello_world.rs --cfg jit --target "$HOST_TRIPLE"
+        CG_CLIF_JIT_ARGS="abc bcd" $MY_RUSTC -Zunstable-options -Cllvm-args=mode=jit-lazy -Cprefer-dynamic example/mini_core_hello_world.rs --cfg jit --target "$HOST_TRIPLE"
     else
         echo "[JIT] mini_core_hello_world (skipped)"
     fi
@@ -44,10 +44,10 @@ function base_sysroot_tests() {
 
     if [[ "$JIT_SUPPORTED" = "1" ]]; then
         echo "[JIT] std_example"
-        $MY_RUSTC -Cllvm-args=mode=jit -Cprefer-dynamic example/std_example.rs --target "$HOST_TRIPLE"
+        $MY_RUSTC -Zunstable-options -Cllvm-args=mode=jit -Cprefer-dynamic example/std_example.rs --target "$HOST_TRIPLE"
 
         echo "[JIT-lazy] std_example"
-        $MY_RUSTC -Cllvm-args=mode=jit-lazy -Cprefer-dynamic example/std_example.rs --target "$HOST_TRIPLE"
+        $MY_RUSTC -Zunstable-options -Cllvm-args=mode=jit-lazy -Cprefer-dynamic example/std_example.rs --target "$HOST_TRIPLE"
     else
         echo "[JIT] std_example (skipped)"
     fi
diff --git a/src/lib.rs b/src/lib.rs
index c7b3ad96048..366b9a7e24c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -184,6 +184,9 @@ impl CodegenBackend for CraneliftCodegenBackend {
         let config = if let Some(config) = self.config.clone() {
             config
         } else {
+            if !tcx.sess.unstable_options() && !tcx.sess.opts.cg.llvm_args.is_empty() {
+                tcx.sess.fatal("`-Z unstable-options` must be passed to allow configuring cg_clif");
+            }
             BackendConfig::from_opts(&tcx.sess.opts.cg.llvm_args)
                 .unwrap_or_else(|err| tcx.sess.fatal(&err))
         };