don't try to attach roots for non-config'd targets

Author: fee1-dead

src/cargo/core/compiler/unit_dependencies.rs

@@ -177,16 +177,19 @@ fn attach_std_deps(
     let mut found = false;
     for (unit, deps) in state.unit_dependencies.iter_mut() {
         if !unit.kind.is_host() && !unit.mode.is_run_custom_build() {
-            deps.extend(std_roots[&unit.kind].iter().map(|unit| UnitDep {
-                unit: unit.clone(),
-                unit_for: UnitFor::new_normal(unit.kind),
-                extern_crate_name: unit.pkg.name(),
-                dep_name: None,
-                // TODO: Does this `public` make sense?
-                public: true,
-                noprelude: true,
-            }));
-            found = true;
+            // only attach roots for which the user has requested `build-std` for.
+            if let Some(roots) = std_roots.get(&unit.kind) {
+                deps.extend(roots.iter().map(|unit| UnitDep {
+                    unit: unit.clone(),
+                    unit_for: UnitFor::new_normal(unit.kind),
+                    extern_crate_name: unit.pkg.name(),
+                    dep_name: None,
+                    // TODO: Does this `public` make sense?
+                    public: true,
+                    noprelude: true,
+                }));
+                found = true;
+            }
         }
     }
     // And also include the dependencies of the standard library itself. Don't

tests/build-std/main.rs

@@ -21,7 +21,7 @@
 #![allow(clippy::disallowed_methods)]
 
 use cargo_test_support::prelude::*;
-use cargo_test_support::{basic_manifest, paths, project, rustc_host, str, Execs};
+use cargo_test_support::{basic_manifest, cross_compile, paths, project, rustc_host, str, Execs};
 use std::env;
 use std::path::Path;
 
@@ -441,3 +441,76 @@ fn test_panic_abort() {
         .arg("-Zbuild-std-features=panic_immediate_abort")
         .run();
 }
+
+
+#[cargo_test(build_std_real)]
+fn bindeps() {
+    if !cross_compile::requires_target_installed("aarch64-unknown-none") {
+        return;
+    }
+
+    let p = project()
+        .file(
+            "Cargo.toml",
+            &r#"
+                [package]
+                name = "foo"
+                version = "0.1.0"
+                edition = "2021"
+                authors = []
+                resolver = "2"
+
+                [dependencies]
+                bar = { path = "bar/", artifact = "staticlib", target = "aarch64-unknown-none" }
+            "#,
+        )
+        .file("src/lib.rs", "")
+        .file(
+            "bar/Cargo.toml",
+            r#"
+            [package]
+            name = "bar"
+            version = "0.5.0"
+            edition = "2021"
+
+            [lib]
+            crate-type = ["staticlib"]
+        "#,
+        )
+        .file(
+            "bar/src/lib.rs",
+            r#"
+            #![no_std]
+            pub fn bar() {}
+            #[panic_handler]
+            fn panic(info: &core::panic::PanicInfo) -> ! {
+                loop {}
+            }
+        "#,
+        )
+        .file(
+            ".cargo/config.toml",
+            &format!(
+                r#"
+                [target.aarch64-unknown-none]
+                build-std = ['core']
+                "#
+            ),
+        )
+        .build();
+    let mut build = p.cargo("build -v --lib -Zunstable-options -Zbindeps");
+    build
+        .target_host()
+        .masquerade_as_nightly_cargo(&["build-std"])
+        .with_stderr_data(
+            str![[r#"
+...
+[RUNNING] `rustc --crate-name bar [..]--target aarch64-unknown-none[..]
+[FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
+
+"#]]
+            .unordered(),
+        );
+
+    build.run();
+}

tests/testsuite/standard_lib.rs

@@ -1037,75 +1037,3 @@ error[E0463]: can't find crate for `core`
 
     build.run();
 }
-
-#[cargo_test(build_std_mock)]
-fn bindeps() {
-    if !cross_compile::requires_target_installed("aarch64-unknown-none") {
-        return;
-    }
-
-    let p = project()
-        .file(
-            "Cargo.toml",
-            &r#"
-                [package]
-                name = "foo"
-                version = "0.1.0"
-                edition = "2021"
-                authors = []
-                resolver = "2"
-
-                [dependencies]
-                bar = { path = "bar/", artifact = "staticlib", target = "aarch64-unknown-none" }
-            "#,
-        )
-        .file("src/lib.rs", "")
-        .file(
-            "bar/Cargo.toml",
-            r#"
-            [package]
-            name = "bar"
-            version = "0.5.0"
-            edition = "2021"
-
-            [lib]
-            crate-type = ["staticlib"]
-        "#,
-        )
-        .file(
-            "bar/src/lib.rs",
-            r#"
-            #![no_std]
-            pub fn bar() {}
-            #[panic_handler]
-            fn panic(info: &core::panic::PanicInfo) -> ! {
-                loop {}
-            }
-        "#,
-        )
-        .file(
-            ".cargo/config.toml",
-            &format!(
-                r#"
-                [target.aarch64-unknown-none]
-                build-std = ['core']
-                "#
-            ),
-        )
-        .build();
-    let mut build = p.cargo("build -v --lib -Zunstable-options -Zbindeps");
-    build
-        .target_host()
-        .masquerade_as_nightly_cargo(&["build-std"])
-        .with_stderr_data(
-            str![[r#"
-...
-[RUNNING] `rustc --crate-name bar [..]--target aarch64-unknown-none[..]
-[FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s
-
-"#]]
-            .unordered(),
-        );
-
-    build.run();
-}