Auto merge of rust-lang#2576 - RalfJung:no-more-vergen, r=RalfJung

Author: RalfJung

cargo-miri/Cargo.lock

@@ -30,4 +30,4 @@ rustc-workspace-hack = "1.0.0"
 serde = { version = "*", features = ["derive"] }
 
 [build-dependencies]
-vergen = { version = "7", default_features = false, features = ["git"] }
+rustc_tools_util = "0.2"

cargo-miri/Cargo.toml

@@ -1,11 +1,13 @@
-use vergen::vergen;
-
 fn main() {
     // Don't rebuild miri when nothing changed.
     println!("cargo:rerun-if-changed=build.rs");
-    // vergen
-    let mut gen_config = vergen::Config::default();
-    *gen_config.git_mut().sha_kind_mut() = vergen::ShaKind::Short;
-    *gen_config.git_mut().commit_timestamp_kind_mut() = vergen::TimestampKind::DateOnly;
-    vergen(gen_config).ok(); // Ignore failure (in case we are built outside a git repo)
+    // gather version info
+    println!(
+        "cargo:rustc-env=GIT_HASH={}",
+        rustc_tools_util::get_commit_hash().unwrap_or_default()
+    );
+    println!(
+        "cargo:rustc-env=COMMIT_DATE={}",
+        rustc_tools_util::get_commit_date().unwrap_or_default()
+    );
 }

cargo-miri/build.rs

@@ -1,7 +1,6 @@
 //! Implements the various phases of `cargo miri run/test`.
 
 use std::env;
-use std::fmt::Write as _;
 use std::fs::{self, File};
 use std::io::BufReader;
 use std::path::PathBuf;
@@ -39,17 +38,13 @@ fn show_help() {
 }
 
 fn show_version() {
-    let mut version = format!("miri {}", env!("CARGO_PKG_VERSION"));
-    // Only use `option_env` on vergen variables to ensure the build succeeds
-    // when vergen failed to find the git info.
-    if let Some(sha) = option_env!("VERGEN_GIT_SHA_SHORT") {
-        // This `unwrap` can never fail because if VERGEN_GIT_SHA_SHORT exists, then so does
-        // VERGEN_GIT_COMMIT_DATE.
-        #[allow(clippy::option_env_unwrap)]
-        write!(&mut version, " ({} {})", sha, option_env!("VERGEN_GIT_COMMIT_DATE").unwrap())
-            .unwrap();
+    print!("miri {}", env!("CARGO_PKG_VERSION"));
+    let version = format!("{} {}", env!("GIT_HASH"), env!("COMMIT_DATE"));
+    if version.len() > 1 {
+        // If there is actually something here, print it.
+        print!(" ({version})");
     }
-    println!("{}", version);
+    println!();
 }
 
 fn forward_patched_extern_arg(args: &mut impl Iterator<Item = String>, cmd: &mut Command) {