Auto merge of #5355 - djc:target-info-no-context, r=matklad

Make it possible to construct TargetInfo without Context

This should make stuff like #5349 easier.

src/cargo/core/compiler/context/compilation_files.rs

@@ -265,7 +265,7 @@ impl<'a, 'cfg: 'a> CompilationFiles<'a, 'cfg> {
                         crate_type,
                         flavor,
                         unit.target.kind(),
-                        cx.target_triple(),
+                        cx.build_config.target_triple(),
                     )?;
 
                     match file_types {
@@ -321,14 +321,14 @@ impl<'a, 'cfg: 'a> CompilationFiles<'a, 'cfg> {
                      does not support these crate types",
                     unsupported.join(", "),
                     unit.pkg,
-                    cx.target_triple()
+                    cx.build_config.target_triple()
                 )
             }
             bail!(
                 "cannot compile `{}` as the target `{}` does not \
                  support any of the output crate types",
                 unit.pkg,
-                cx.target_triple()
+                cx.build_config.target_triple()
             );
         }
         info!("Target filenames: {:?}", ret);
@@ -380,7 +380,7 @@ fn compute_metadata<'a, 'cfg>(
     let __cargo_default_lib_metadata = env::var("__CARGO_DEFAULT_LIB_METADATA");
     if !(unit.profile.test || unit.profile.check)
         && (unit.target.is_dylib() || unit.target.is_cdylib()
-            || (unit.target.is_bin() && cx.target_triple().starts_with("wasm32-")))
+            || (unit.target.is_bin() && cx.build_config.target_triple().starts_with("wasm32-")))
         && unit.pkg.package_id().source_id().is_path()
         && __cargo_default_lib_metadata.is_err()
     {

src/cargo/core/compiler/context/mod.rs

@@ -125,13 +125,31 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             None => Client::new(build_config.jobs as usize - 1)
                 .chain_err(|| "failed to create jobserver")?,
         };
+
+        let (host_info, target_info) = {
+            let _p = profile::start("Context::probe_target_info");
+            debug!("probe_target_info");
+            let host_target_same = match build_config.requested_target {
+                Some(ref s) if s != &config.rustc()?.host => false,
+                _ => true,
+            };
+
+            let host_info = TargetInfo::new(config, &build_config, Kind::Host)?;
+            let target_info = if host_target_same {
+                host_info.clone()
+            } else {
+                TargetInfo::new(config, &build_config, Kind::Target)?
+            };
+            (host_info, target_info)
+        };
+
         let mut cx = Context {
             ws,
             resolve,
             packages,
             config,
-            target_info: TargetInfo::default(),
-            host_info: TargetInfo::default(),
+            target_info,
+            host_info,
             compilation: Compilation::new(config),
             build_state: Arc::new(BuildState::new(&build_config)),
             build_config,
@@ -150,7 +168,8 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             files: None,
         };
 
-        cx.probe_target_info()?;
+        cx.compilation.host_dylib_path = cx.host_info.sysroot_libdir.clone();
+        cx.compilation.target_dylib_path = cx.target_info.sysroot_libdir.clone();
         Ok(cx)
     }
 
@@ -283,7 +302,7 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
                 self.compilation.native_dirs.insert(dir.clone());
             }
         }
-        self.compilation.target = self.target_triple().to_string();
+        self.compilation.target = self.build_config.target_triple().to_string();
         Ok(self.compilation)
     }
 
@@ -341,27 +360,6 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
         Ok(())
     }
 
-    /// Ensure that we've collected all target-specific information to compile
-    /// all the units mentioned in `units`.
-    fn probe_target_info(&mut self) -> CargoResult<()> {
-        let _p = profile::start("Context::probe_target_info");
-        debug!("probe_target_info");
-        let host_target_same = match self.requested_target() {
-            Some(s) if s != self.config.rustc()?.host => false,
-            _ => true,
-        };
-
-        self.host_info = TargetInfo::new(self, Kind::Host)?;
-        self.target_info = if host_target_same {
-            self.host_info.clone()
-        } else {
-            TargetInfo::new(self, Kind::Target)?
-        };
-        self.compilation.host_dylib_path = self.host_info.sysroot_libdir.clone();
-        self.compilation.target_dylib_path = self.target_info.sysroot_libdir.clone();
-        Ok(())
-    }
-
     /// Builds up the `used_in_plugin` internal to this context from the list of
     /// top-level units.
     ///
@@ -401,22 +399,6 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
         self.files.as_mut().unwrap()
     }
 
-    /// Return the host triple for this context
-    pub fn host_triple(&self) -> &str {
-        &self.build_config.host_triple
-    }
-
-    /// Return the target triple which this context is targeting.
-    pub fn target_triple(&self) -> &str {
-        self.requested_target()
-            .unwrap_or_else(|| self.host_triple())
-    }
-
-    /// Requested (not actual) target for the build
-    pub fn requested_target(&self) -> Option<&str> {
-        self.build_config.requested_target.as_ref().map(|s| &s[..])
-    }
-
     /// Return the filenames that the given target for the given profile will
     /// generate as a list of 3-tuples (filename, link_dst, linkable)
     ///
@@ -458,8 +440,8 @@ impl<'a, 'cfg> Context<'a, 'cfg> {
             None => return true,
         };
         let (name, info) = match kind {
-            Kind::Host => (self.host_triple(), &self.host_info),
-            Kind::Target => (self.target_triple(), &self.target_info),
+            Kind::Host => (self.build_config.host_triple.as_ref(), &self.host_info),
+            Kind::Target => (self.build_config.target_triple(), &self.target_info),
         };
         platform.matches(name, info.cfg())
     }

src/cargo/core/compiler/context/target_info.rs

@@ -3,12 +3,12 @@ use std::collections::hash_map::{Entry, HashMap};
 use std::path::PathBuf;
 use std::str::{self, FromStr};
 
-use super::{env_args, Context};
-use util::{CargoResult, CargoResultExt, Cfg, ProcessBuilder};
+use super::{env_args, BuildConfig};
+use util::{CargoResult, CargoResultExt, Cfg, Config, ProcessBuilder};
 use core::TargetKind;
 use super::Kind;
 
-#[derive(Clone, Default)]
+#[derive(Clone)]
 pub struct TargetInfo {
     crate_type_process: Option<ProcessBuilder>,
     crate_types: RefCell<HashMap<String, Option<(String, String)>>>,
@@ -51,9 +51,9 @@ impl FileType {
 }
 
 impl TargetInfo {
-    pub fn new(cx: &Context, kind: Kind) -> CargoResult<TargetInfo> {
-        let rustflags = env_args(cx.config, &cx.build_config, None, kind, "RUSTFLAGS")?;
-        let mut process = cx.config.rustc()?.process();
+    pub fn new(config: &Config, build_config: &BuildConfig, kind: Kind) -> CargoResult<TargetInfo> {
+        let rustflags = env_args(config, build_config, None, kind, "RUSTFLAGS")?;
+        let mut process = config.rustc()?.process();
         process
             .arg("-")
             .arg("--crate-name")
@@ -63,7 +63,7 @@ impl TargetInfo {
             .env_remove("RUST_LOG");
 
         if kind == Kind::Target {
-            process.arg("--target").arg(&cx.target_triple());
+            process.arg("--target").arg(&build_config.target_triple());
         }
 
         let crate_type_process = process.clone();
@@ -115,7 +115,7 @@ impl TargetInfo {
             } else {
                 rustlib.push("lib");
                 rustlib.push("rustlib");
-                rustlib.push(cx.target_triple());
+                rustlib.push(build_config.target_triple());
                 rustlib.push("lib");
                 sysroot_libdir = Some(rustlib);
             }

src/cargo/core/compiler/custom_build.rs

@@ -127,8 +127,8 @@ fn build_work<'a, 'cfg>(cx: &mut Context<'a, 'cfg>, unit: &Unit<'a>) -> CargoRes
         .env(
             "TARGET",
             &match unit.kind {
-                Kind::Host => cx.host_triple(),
-                Kind::Target => cx.target_triple(),
+                Kind::Host => &cx.build_config.host_triple,
+                Kind::Target => cx.build_config.target_triple(),
             },
         )
         .env("DEBUG", &profile.debuginfo.is_some().to_string())
@@ -141,7 +141,7 @@ fn build_work<'a, 'cfg>(cx: &mut Context<'a, 'cfg>, unit: &Unit<'a>) -> CargoRes
                 "debug"
             },
         )
-        .env("HOST", cx.host_triple())
+        .env("HOST", &cx.build_config.host_triple)
         .env("RUSTC", &cx.config.rustc()?.path)
         .env("RUSTDOC", &*cx.config.rustdoc()?)
         .inherit_jobserver(&cx.jobserver);

src/cargo/core/compiler/mod.rs

@@ -141,6 +141,12 @@ impl BuildConfig {
             ..Default::default()
         })
     }
+
+    pub fn target_triple(&self) -> &str {
+        self.requested_target
+            .as_ref()
+            .unwrap_or_else(|| &self.host_triple)
+    }
 }
 
 /// Information required to build for a target
@@ -733,7 +739,7 @@ fn rustdoc<'a, 'cfg>(cx: &mut Context<'a, 'cfg>, unit: &Unit<'a>) -> CargoResult
     add_path_args(cx, unit, &mut rustdoc);
 
     if unit.kind != Kind::Host {
-        if let Some(target) = cx.requested_target() {
+        if let Some(ref target) = cx.build_config.requested_target {
             rustdoc.arg("--target").arg(target);
         }
     }
@@ -994,7 +1000,10 @@ fn build_base_args<'a, 'cfg>(
             cmd,
             "--target",
             "",
-            cx.requested_target().map(|s| s.as_ref()),
+            cx.build_config
+                .requested_target
+                .as_ref()
+                .map(|s| s.as_ref()),
         );
     }
 

src/cargo/ops/resolve.rs

@@ -213,7 +213,6 @@ pub fn resolve_with_previous<'a, 'cfg>(
         registry.lock_patches();
     }
 
-
     for member in ws.members() {
         registry.add_sources(&[member.package_id().source_id().clone()])?;
     }
@@ -223,12 +222,18 @@ pub fn resolve_with_previous<'a, 'cfg>(
         let mut members = Vec::new();
         match method {
             Method::Everything => members.extend(ws.members()),
-            Method::Required { features, all_features, uses_default_features, .. } => {
+            Method::Required {
+                features,
+                all_features,
+                uses_default_features,
+                ..
+            } => {
                 if specs.len() > 1 && !features.is_empty() {
                     bail!("cannot specify features for more than one package");
                 }
                 members.extend(
-                    ws.members().filter(|m| specs.iter().any(|spec| spec.matches(m.package_id())))
+                    ws.members()
+                        .filter(|m| specs.iter().any(|spec| spec.matches(m.package_id()))),
                 );
                 // Edge case: running `cargo build -p foo`, where `foo` is not a member
                 // of current workspace. Add all packages from workspace to get `foo`
@@ -293,7 +298,6 @@ pub fn resolve_with_previous<'a, 'cfg>(
         }
     };
 
-
     let root_replace = ws.root_replace();
 
     let replace = match previous {

tests/testsuite/features.rs

@@ -1664,39 +1664,46 @@ fn combining_features_and_package() {
             main = []
         "#,
         )
-        .file("foo/src/main.rs", r#"
+        .file(
+            "foo/src/main.rs",
+            r#"
             #[cfg(feature = "main")]
             fn main() {}
-        "#)
+        "#,
+        )
         .build();
 
     assert_that(
         p.cargo("build -Z package-features --all --features main")
             .masquerade_as_nightly_cargo(),
-        execs().with_status(101).with_stderr_contains("\
-[ERROR] cannot specify features for more than one package"
+        execs().with_status(101).with_stderr_contains(
+            "\
+             [ERROR] cannot specify features for more than one package",
         ),
     );
 
     assert_that(
         p.cargo("build -Z package-features --package dep --features main")
             .masquerade_as_nightly_cargo(),
-        execs().with_status(101).with_stderr_contains("\
-[ERROR] cannot specify features for packages outside of workspace"
+        execs().with_status(101).with_stderr_contains(
+            "\
+             [ERROR] cannot specify features for packages outside of workspace",
         ),
     );
     assert_that(
         p.cargo("build -Z package-features --package dep --all-features")
             .masquerade_as_nightly_cargo(),
-        execs().with_status(101).with_stderr_contains("\
-[ERROR] cannot specify features for packages outside of workspace"
+        execs().with_status(101).with_stderr_contains(
+            "\
+             [ERROR] cannot specify features for packages outside of workspace",
         ),
     );
     assert_that(
         p.cargo("build -Z package-features --package dep --no-default-features")
             .masquerade_as_nightly_cargo(),
-        execs().with_status(101).with_stderr_contains("\
-[ERROR] cannot specify features for packages outside of workspace"
+        execs().with_status(101).with_stderr_contains(
+            "\
+             [ERROR] cannot specify features for packages outside of workspace",
         ),
     );