Build rust-analyzer with specific target for install/pgo xtask

Author: itsjunetime

xtask/src/install.rs

@@ -145,12 +145,12 @@ fn install_server(sh: &Shell, opts: ServerOpt) -> anyhow::Result<()> {
     );
 
     if let Some(train_crate) = opts.pgo {
+        let target = detect_target(sh);
         let build_cmd = cmd!(
             sh,
-            "cargo build --manifest-path ./crates/rust-analyzer/Cargo.toml --bin rust-analyzer --profile={profile} --locked --features force-always-assert {features...}"
+            "cargo build --manifest-path ./crates/rust-analyzer/Cargo.toml --bin rust-analyzer --target {target} --profile={profile} --locked --features force-always-assert {features...}"
         );
 
-        let target = detect_target(sh);
         let profile = crate::pgo::gather_pgo_profile(sh, build_cmd, &target, train_crate)?;
         install_cmd = crate::pgo::apply_pgo_to_cmd(install_cmd, &profile);
     }

xtask/src/pgo.rs

@@ -60,7 +60,12 @@ pub(crate) fn gather_pgo_profile<'a>(
         } else {
             None
         }
-    });
+    }).collect::<Vec<_>>();
+
+    if profile_files.is_empty() {
+        anyhow::bail!("rust-analyzer analysis-stats produced no pgo files. This is a bug in rust-analyzer; please file an issue.");
+    }
+
     cmd!(sh, "{llvm_profdata} merge {profile_files...} -o {merged_profile}").run().context(
         "cannot merge PGO profiles. Do you have the rustup `llvm-tools` component installed?",
     )?;