Merge pull request #71 from rust-osdev/embed-bitcode

Set `-Clinker-plugin-lto` for the sysroot build

CHANGELOG.md

@@ -5,6 +5,10 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 ## Unreleased
 
+- Set `-Clinker-plugin-lto` for the sysroot build ([#71](https://github.com/rust-osdev/cargo-xbuild/pull/71))
+  - Second try to fix missing bitcode error for LTO builds (see [#69](https://github.com/rust-osdev/cargo-xbuild/issues/69))
+  - Reverts "Enable lto for sysroot build to fix missing bitcode error ([#70](https://github.com/rust-osdev/cargo-xbuild/pull/70))"
+
 ## 0.5.30 - 2020-05-11
 
 - Enable lto for sysroot build to fix missing bitcode error ([#70](https://github.com/rust-osdev/cargo-xbuild/pull/70))

src/cargo.rs

@@ -194,11 +194,11 @@ pub fn config() -> Result<Option<Config>> {
     }
 }
 
-pub struct Profile {
-    table: Value,
+pub struct Profile<'t> {
+    table: &'t Value,
 }
 
-impl Profile {
+impl<'t> Profile<'t> {
     pub fn hash<H>(&self, hasher: &mut H)
     where
         H: Hasher,
@@ -218,13 +218,9 @@ impl Profile {
 
         v.to_string().hash(hasher);
     }
-
-    pub fn set_lto(&mut self) {
-        self.table.as_table_mut().expect("[profile.release] not a table").insert("lto".into(), Value::Boolean(true));
-    }
 }
 
-impl fmt::Display for Profile {
+impl<'t> fmt::Display for Profile<'t> {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let mut map = toml::map::Map::new();
         map.insert("profile".to_owned(), {
@@ -247,7 +243,7 @@ impl Toml {
         self.table
             .get("profile")
             .and_then(|v| v.get("release"))
-            .map(|t| Profile { table: t.clone() })
+            .map(|t| Profile { table: t })
     }
 }
 

src/sysroot.rs

@@ -74,11 +74,8 @@ fn build_crate(
 
     let target_dir = td.join("target");
 
-    if let Some(mut profile) = ctoml.profile() {
-        profile.set_lto();
+    if let Some(profile) = ctoml.profile() {
         stoml.push_str(&profile.to_string())
-    } else {
-        stoml.push_str("[profile.release]\nlto = true");
     }
 
     util::write(&td.join("Cargo.toml"), &stoml)?;
@@ -87,7 +84,7 @@ fn build_crate(
 
     let cargo = std::env::var("CARGO").unwrap_or("cargo".to_string());
     let mut cmd = Command::new(cargo);
-    cmd.env_remove("RUSTFLAGS");
+    cmd.env("RUSTFLAGS", "-Clinker-plugin-lto");
     cmd.env("CARGO_TARGET_DIR", &target_dir);
     cmd.env("__CARGO_DEFAULT_LIB_METADATA", "XARGO");