delete core stuff

And use --release and respect rustflags.

Just to make doubly-sure that even in the future, a build will be done
instead of check.

src/build.rs

@@ -2,6 +2,7 @@ use std::{
     fmt::{Debug, Display},
     num::NonZeroUsize,
     path::Path,
+    process::Output,
     time::{Duration, Instant, SystemTime},
 };
 
@@ -233,14 +234,9 @@ async fn build_single_target(db: &Db, nightly: &str, target: &str, mode: BuildMo
 
     let start_time = Instant::now();
 
-    let result = build_target(
-        tmpdir.path(),
-        &Toolchain::from_nightly(nightly),
-        target,
-        mode,
-    )
-    .await
-    .wrap_err("running build")?;
+    let result = build_target(tmpdir.path(), &Toolchain::from_nightly(nightly), target)
+        .await
+        .wrap_err("running build")?;
 
     db.insert(FullBuildInfo {
         nightly: nightly.into(),
@@ -272,16 +268,19 @@ struct BuildResult {
 }
 
 /// Build a target core in a temporary directory and see whether it passes or not.
-async fn build_target(
-    tmpdir: &Path,
-    toolchain: &Toolchain,
-    target: &str,
-    mode: BuildMode,
-) -> Result<BuildResult> {
+async fn build_target(tmpdir: &Path, toolchain: &Toolchain, target: &str) -> Result<BuildResult> {
     let mut rustflags = None;
 
     let init = Command::new("cargo")
-        .args(["init", "--lib", "--name", "target-test"])
+        .arg(format!("+{toolchain}"))
+        .args([
+            "init",
+            "--lib",
+            "--name",
+            "target-test",
+            "--edition",
+            "2015",
+        ])
         .current_dir(tmpdir)
         .output()
         .await
@@ -294,41 +293,58 @@ async fn build_target(
     std::fs::write(&librs, "#![no_std]\n")
         .wrap_err_with(|| format!("writing to {}", librs.display()))?;
 
-    let mut cmd = Command::new("cargo");
+    async fn run(
+        toolchain: &Toolchain,
+        target: &str,
+        rustflags: &mut Option<String>,
+        tmpdir: &Path,
+        build_std: &str,
+    ) -> Result<Output> {
+        let mut cmd = Command::new("cargo");
+        cmd.arg(format!("+{toolchain}"))
+            .args(["build", "--release", "-j1"])
+            .arg(build_std)
+            .args(["--target", target]);
 
-    match mode {
-        BuildMode::Core => {
-            cmd.arg(format!("+{toolchain}"))
-                .args(["build", "-Zbuild-std=core", "--release"])
-                .args(["--target", target]);
+        let extra_flags = CUSTOM_CORE_FLAGS
+            .iter()
+            .find(|flags| flags.target == target);
 
-            let extra_flags = CUSTOM_CORE_FLAGS
-                .iter()
-                .find(|flags| flags.target == target);
-
-            if let Some(extra_flags) = extra_flags {
-                let flags = extra_flags.flags.join(" ");
-                cmd.env("RUSTFLAGS", &flags);
-                rustflags = Some(flags);
-            }
+        if let Some(extra_flags) = extra_flags {
+            let flags = extra_flags.flags.join(" ");
+            cmd.env("RUSTFLAGS", &flags);
+            *rustflags = Some(flags);
         }
-        BuildMode::Std => {
-            cmd.arg(format!("+{toolchain}"))
-                .args(["check", "-Zbuild-std"])
-                .args(["--target", target]);
-        }
-    };
 
-    let output = cmd
-        .current_dir(tmpdir)
-        .output()
-        .await
-        .wrap_err("spawning cargo build")?;
+        cmd.current_dir(tmpdir)
+            .output()
+            .await
+            .wrap_err("spawning cargo build")
+    }
 
-    let stderr = String::from_utf8(output.stderr).wrap_err("cargo stderr utf8")?;
+    let mut output = run(toolchain, target, &mut rustflags, tmpdir, "-Zbuild-std").await?;
+    let mut stderr = String::from_utf8(output.stderr).wrap_err("cargo stderr utf8")?;
 
     let status = if output.status.success() {
         Status::Pass
+    // older cargo (before 2024-12-15) is clueless about std support
+    } else if stderr.contains("building std is not supported") {
+        info!("Retrying build because std is not supported");
+        output = run(
+            toolchain,
+            target,
+            &mut rustflags,
+            tmpdir,
+            "-Zbuild-std=core",
+        )
+        .await?;
+        stderr = String::from_utf8(output.stderr).wrap_err("cargo stderr utf8")?;
+
+        if output.status.success() {
+            Status::Pass
+        } else {
+            Status::Error
+        }
     } else {
         Status::Error
     };

src/db.rs

@@ -17,16 +17,13 @@ pub static MIGRATOR: Migrator = sqlx::migrate!();
 #[derive(Debug, Clone, Copy, sqlx::Type, Serialize, PartialEq, Eq, Hash)]
 #[sqlx(rename_all = "kebab-case")]
 pub enum BuildMode {
-    /// `build -Zbuild-std=core`
-    Core,
-    /// `check -Zbuild-std`
+    /// `build --release -Zbuild-std`
     Std,
 }
 
 impl Display for BuildMode {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
-            Self::Core => f.write_str("core"),
             Self::Std => f.write_str("std"),
         }
     }

src/nightlies.rs

@@ -44,7 +44,7 @@ impl Nightlies {
 
         self.all
             .iter()
-            .flat_map(|nightly| [(nightly, BuildMode::Core), (nightly, BuildMode::Std)])
+            .flat_map(|nightly| [(nightly, BuildMode::Std)])
             .find(|(nightly, mode)| {
                 !already_finished.contains(&FinishedNightly {
                     nightly: (*nightly).to_owned(),

src/web.rs

@@ -44,14 +44,14 @@ impl<'de> serde::Deserialize<'de> for LegacyBuildMode {
     {
         let s = String::deserialize(deserializer)?;
         match s.as_str() {
-            "core" => Ok(LegacyBuildMode(BuildMode::Core)),
+            "core" => Ok(LegacyBuildMode(BuildMode::Std)),
             "std" => Ok(LegacyBuildMode(BuildMode::Std)),
             // This mode used to be called "miri-std" but it has been renamed to "std" using build-std.
             // Allow the old value to keep links working but map it to std.
             "miri-std" => Ok(LegacyBuildMode(BuildMode::Std)),
-            _ => Err(serde::de::Error::custom(format!(
-                "invalid build mode, expected 'core', 'std', or 'miri-std'"
-            ))),
+            _ => Err(serde::de::Error::custom(
+                "invalid build mode, expected 'core', 'std', or 'miri-std'".to_owned(),
+            )),
         }
     }
 }
@@ -85,7 +85,7 @@ async fn web_build(State(state): State<AppState>, Query(query): Query<BuildQuery
         .build_status_full(
             &query.nightly,
             &query.target,
-            query.mode.map(|mode| mode.0).unwrap_or(BuildMode::Core),
+            query.mode.map(|mode| mode.0).unwrap_or(BuildMode::Std),
         )
         .await
     {
@@ -144,26 +144,14 @@ async fn web_target(State(state): State<AppState>, Query(query): Query<TargetQue
 
     match state.db.history_for_target(&query.target).await {
         Ok(builds) => {
-            let latest_core = builds
+            let latest_std = builds
                 .iter()
-                .filter(|build| build.mode == BuildMode::Core)
-                .max_by_key(|elem| elem.nightly.clone());
-            let latest_miri = builds
-                .iter()
-                .filter(|build| build.mode == BuildMode::Core)
+                .filter(|build| build.mode == BuildMode::Std)
                 .max_by_key(|elem| elem.nightly.clone());
 
-            let status = match (latest_core, latest_miri) {
-                (Some(core), Some(std)) => {
-                    if core.status == Status::Error || std.status == Status::Error {
-                        Status::Error
-                    } else {
-                        Status::Pass
-                    }
-                    .to_string()
-                }
-                (Some(one), None) | (None, Some(one)) => one.status.to_string(),
-                (None, None) => "missing".to_owned(),
+            let status = match latest_std {
+                Some(one) => one.status.to_string(),
+                None => "missing".to_owned(),
             };
 
             let mut builds_grouped =
@@ -171,7 +159,6 @@ async fn web_target(State(state): State<AppState>, Query(query): Query<TargetQue
             for build in builds {
                 let v = builds_grouped.entry(build.nightly.clone()).or_default();
                 match build.mode {
-                    BuildMode::Core => v.0 = Some(build),
                     BuildMode::Std => v.1 = Some(build),
                 }
             }
@@ -217,9 +204,7 @@ async fn web_nightly(State(state): State<AppState>, Query(query): Query<NightlyQ
         nightly: String,
         version: &'static str,
         builds: Vec<(String, Option<BuildInfo>, Option<BuildInfo>)>,
-        core_failures: usize,
         std_failures: usize,
-        core_broken: Option<String>,
         std_broken: Option<String>,
         showing_failures: bool,
     }
@@ -234,17 +219,14 @@ async fn web_nightly(State(state): State<AppState>, Query(query): Query<NightlyQ
                 for build in &builds {
                     let v = builds_grouped.entry(build.target.clone()).or_default();
                     match build.mode {
-                        BuildMode::Core => v.0 = Some(build.clone()),
                         BuildMode::Std => v.1 = Some(build.clone()),
                     }
                 }
 
                 let mut std_failures = 0;
-                let mut core_failures = 0;
                 for build in builds {
                     if build.status == Status::Error {
                         match build.mode {
-                            BuildMode::Core => core_failures += 1,
                             BuildMode::Std => std_failures += 1,
                         }
                     }
@@ -260,10 +242,6 @@ async fn web_nightly(State(state): State<AppState>, Query(query): Query<NightlyQ
                     .collect::<Vec<_>>();
                 builds.sort_by_cached_key(|build| build.0.clone());
 
-                let core_broken = info
-                    .iter()
-                    .find(|info| info.mode == BuildMode::Core && info.is_broken)
-                    .and_then(|info| info.broken_error.clone());
                 let std_broken = info
                     .iter()
                     .find(|info| info.mode == BuildMode::Std && info.is_broken)
@@ -274,8 +252,6 @@ async fn web_nightly(State(state): State<AppState>, Query(query): Query<NightlyQ
                     version: crate::VERSION,
                     builds,
                     std_failures,
-                    core_failures,
-                    core_broken,
                     std_broken,
                     showing_failures: filter_failures,
                 };

templates/nightly.html

@@ -10,27 +10,13 @@
     <h1>Nightly build state for {{nightly}}</h1>
     <a href="/">Home</a>
     <p>
-      This contains the status of this nightly. Core is built with
-      <code>cargo build --release -Zbuild-std=core</code>. This checks that
-      codegen/linking of core works, but does not check whether std builds.
-    </p>
-    <p>
-      std is being built with <code>cargo check -Zbuild-std</code>. If a target
-      does not support std, the std column represents core/alloc. This checks
-      that std checks (on targets that have it) but does not check whether
-      codegen/linking works.
+      The build is performned with <code>cargo build --release -Zbuild-std</code> for a library crate.
 
-      For older builds, <code>cargo miri setup</code> was used instead.
-    </p>
-    {% if let Some(core_broken) = core_broken %}
-    <p>
-      ⚠️ The core build is broken in general for this nightly, so no data is available ⚠️
+      This checks whether everything builds successfully (excluding binary linking, which often requires complex toolchains).
+      For no-std targets, Cargo's build-std logic is used for figuring out whether to build std or not.
+      On older targets (older than November 2024) this does not always work reliably, so some failed std builds there are simply no-std targets.
     </p>
 
-    <pre>
-      {{core_broken}}
-    </pre>
-    {% endif %}
     {% if let Some(std_broken) = std_broken %}
     <p>
       ⚠️ The std build is broken for this nightly, so no data is available ⚠️
@@ -43,8 +29,6 @@
 
     <p>
       <dl>
-        <dt>core failures</dt>
-        <dd>{{core_failures}}</dd>
         <dt>std failures</dt>
         <dd>{{std_failures}}</dd>
       </dl>
@@ -61,21 +45,12 @@
     <table>
       <tr>
         <th>nightly</th>
-        <th>core<br>codegen</th>
-        <th>std<br>check</th>
+        <th>std<br>build</th>
       </tr>
       {% for build in builds %}
       <tr>
         <td><a href="/target?target={{build.0}}">{{ build.0 }}</a></td>
-        {% match build.1 %} {% when Some with (build) %}
-        <td class="build-cell">
-          <a class="build-info-a" href="{{ build.link() }}">
-            {{ build.status.to_emoji() }}
-          </a>
-        </td>
-        {% when None %}
-        <td class="missing"></td>
-        {% endmatch %} {% match build.2 %} {% when Some with (build) %}
+        {% match build.2 %} {% when Some with (build) %}
         <td class="build-cell">
           <a class="build-info-a" href="{{ build.link() }}">
             <span> {{ build.status.to_emoji() }} </span>

templates/target.html

@@ -23,12 +23,13 @@
       codegen/linking of core works, but does not check whether std builds.
     </p>
     <p>
-      std is being built with <code>cargo check -Zbuild-std</code>. If a target
-      does not support std, the std column represents core/alloc. This checks
-      that std checks (on targets that have it) but does not check whether
-      codegen/linking works.
-
-      For older builds, <code>cargo miri setup</code> was used instead.
+      The build is performned with
+      <code>cargo build --release -Zbuild-std</code> for a library crate. This
+      checks whether everything builds successfully (excluding binary linking,
+      which often requires complex toolchains). For no-std targets, Cargo's
+      build-std logic is used for figuring out whether to build std or not. On
+      older targets (older than November 2024) this does not always work
+      reliably, so some failed std builds there are simply no-std targets.
     </p>
     {% if showing_failures %}
     <p>
@@ -42,21 +43,12 @@
     <table>
       <tr>
         <th>nightly</th>
-        <th>core<br />codegen</th>
-        <th>std<br />check</th>
+        <th>std<br />build</th>
       </tr>
       {% for build in builds %}
       <tr>
         <td><a href="/nightly?nightly={{build.0}}">{{ build.0 }}</a></td>
-        {% match build.1 %} {% when Some with (build) %}
-        <td class="build-cell">
-          <a class="build-info-a" href="{{ build.link() }}">
-            {{ build.status.to_emoji() }}
-          </a>
-        </td>
-        {% when None %}
-        <td class="missing"></td>
-        {% endmatch %} {% match build.2 %} {% when Some with (build) %}
+        {% match build.2 %} {% when Some with (build) %}
         <td class="build-cell">
           <a class="build-info-a" href="{{ build.link() }}">
             <span> {{ build.status.to_emoji() }} </span>