./miri build: also build tests, to avoid rebuilds later

src/tools/miri/Cargo.lock

@@ -542,7 +542,6 @@ dependencies = [
  "rand",
  "regex",
  "rustc_version",
- "serde",
  "smallvec",
  "ui_test",
 ]

src/tools/miri/Cargo.toml

@@ -39,11 +39,8 @@ libloading = "0.8"
 colored = "2"
 ui_test = "0.21.1"
 rustc_version = "0.4"
-# Features chosen to match those required by env_logger, to avoid rebuilds
-regex = { version = "1.5.5", default-features = false, features = ["perf", "std"] }
+regex = "1.5.5"
 lazy_static = "1.4.0"
-# Require a version of serde without intransparent unreproducible binary blobs.
-serde = { version = "1.0.185", features = ["derive"] }
 
 [package.metadata.rust-analyzer]
 # This crate uses #[feature(rustc_private)].

src/tools/miri/miri-script/src/util.rs

@@ -111,9 +111,11 @@ impl MiriEnv {
     ) -> Result<()> {
         let MiriEnv { toolchain, cargo_extra_flags, .. } = self;
         let quiet_flag = if quiet { Some("--quiet") } else { None };
+        // We build the tests as well, (a) to avoid having rebuilds when building the tests later
+        // and (b) to have more parallelism during the build of Miri and its tests.
         let mut cmd = cmd!(
             self.sh,
-            "cargo +{toolchain} build {cargo_extra_flags...} --manifest-path {manifest_path} {quiet_flag...} {args...}"
+            "cargo +{toolchain} build --bins --tests {cargo_extra_flags...} --manifest-path {manifest_path} {quiet_flag...} {args...}"
         );
         cmd.set_quiet(quiet);
         cmd.run()?;