Pass arguments to x subcommands with --

src/bootstrap/check.rs

@@ -58,9 +58,10 @@ fn args(builder: &Builder<'_>) -> Vec<String> {
         clippy_lint_warn.iter().for_each(|v| clippy_lint_levels.push(format!("-W{}", v)));
         clippy_lint_forbid.iter().for_each(|v| clippy_lint_levels.push(format!("-F{}", v)));
         args.extend(clippy_lint_levels);
+        args.extend(builder.config.free_args.clone());
         args
     } else {
-        vec![]
+        builder.config.free_args.clone()
     }
 }
 

src/bootstrap/config.rs

@@ -97,6 +97,10 @@ pub struct Config {
     pub cmd: Subcommand,
     pub incremental: bool,
     pub dry_run: DryRun,
+    /// Arguments appearing after `--` to be forwarded to tools,
+    /// e.g. `--fix-broken` or test arguments.
+    pub free_args: Vec<String>,
+
     /// `None` if we shouldn't download CI compiler artifacts, or the commit to download if we should.
     #[cfg(not(test))]
     download_rustc_commit: Option<String>,
@@ -866,6 +870,7 @@ impl Config {
         config.keep_stage = flags.keep_stage;
         config.keep_stage_std = flags.keep_stage_std;
         config.color = flags.color;
+        config.free_args = flags.free_args.clone().unwrap_or_default();
         if let Some(value) = flags.deny_warnings {
             config.deny_warnings = value;
         }

src/bootstrap/flags.rs

@@ -80,6 +80,10 @@ pub struct Flags {
     pub llvm_profile_generate: bool,
     pub llvm_bolt_profile_generate: bool,
     pub llvm_bolt_profile_use: Option<String>,
+
+    /// Arguments appearing after `--` to be forwarded to tools,
+    /// e.g. `--fix-broken` or test arguments.
+    pub free_args: Option<Vec<String>>,
 }
 
 #[derive(Debug)]
@@ -156,6 +160,12 @@ impl Default for Subcommand {
 
 impl Flags {
     pub fn parse(args: &[String]) -> Flags {
+        let (args, free_args) = if let Some(pos) = args.iter().position(|s| s == "--") {
+            let (args, free) = args.split_at(pos);
+            (args, Some(free[1..].to_vec()))
+        } else {
+            (args, None)
+        };
         let mut subcommand_help = String::from(
             "\
 Usage: x.py <subcommand> [options] [<paths>...]
@@ -706,6 +716,7 @@ Arguments:
             llvm_profile_generate: matches.opt_present("llvm-profile-generate"),
             llvm_bolt_profile_generate: matches.opt_present("llvm-bolt-profile-generate"),
             llvm_bolt_profile_use: matches.opt_str("llvm-bolt-profile-use"),
+            free_args,
         }
     }
 }

src/bootstrap/run.rs

@@ -183,6 +183,7 @@ impl Step for Miri {
         // Forward arguments.
         miri.arg("--").arg("--target").arg(target.rustc_target_arg());
         miri.args(builder.config.cmd.args());
+        miri.args(&builder.config.free_args);
 
         // miri tests need to know about the stage sysroot
         miri.env("MIRI_SYSROOT", &miri_sysroot);

src/bootstrap/test.rs

@@ -1584,6 +1584,7 @@ note: if you're sure you want to do this, please open an issue as to why. In the
             .collect();
 
         test_args.append(&mut builder.config.cmd.test_args());
+        test_args.extend(builder.config.free_args.iter().map(|s| s.as_str()));
 
         // On Windows, replace forward slashes in test-args by backslashes
         // so the correct filters are passed to libtest