From e78ecd2e70961e64040598a019febec44959f7dd Mon Sep 17 00:00:00 2001
From: Mark Simulacrum <mark.simulacrum@gmail.com>
Date: Thu, 15 Feb 2018 18:01:26 -0700
Subject: [PATCH 1/3] Prevent silently ignoring unmatched paths

Primarily for CI purposes; this is intended to avoid cases where we
update rustbuild and unintentionally make CI stop running some builds to
the arguments being passed no longer applying for some reason.
---
 src/bootstrap/builder.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 001ae7246fdf2..22a128e38e804 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -217,7 +217,7 @@ impl StepDescription {
                 }
 
                 if !attempted_run {
-                    eprintln!("Warning: no rules matched {}.", path.display());
+                    panic!("Error: no rules matched {}.", path.display());
                 }
             }
         }

From 366a65665aed84fda50e4ea8bc905153ffcc1287 Mon Sep 17 00:00:00 2001
From: Mark Simulacrum <mark.simulacrum@gmail.com>
Date: Thu, 15 Feb 2018 18:12:04 -0700
Subject: [PATCH 2/3] Consider paths passed to x.py to be root-relative.

We'd previously assumed that these paths would be relative to the src
dir, and that for example our various CI scripts would, when calling
x.py, use `../x.py build ../src/tools/...` but this isn't the case --
they use `../x.py` without using the relevant source-relative path.

We eventually may want to make this (actually somewhat logical) change,
but this is not that time.
---
 src/bootstrap/builder.rs | 4 ++++
 src/bootstrap/flags.rs   | 8 ++------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 22a128e38e804..7345b284dc70a 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -385,6 +385,10 @@ impl<'a> Builder<'a> {
             Subcommand::Clean { .. } => panic!(),
         };
 
+        if paths[0] == Path::new("nonexistent/path/to/trigger/cargo/metadata") {
+            return;
+        }
+
         let builder = Builder {
             build,
             top_stage: build.config.stage.unwrap_or(2),
diff --git a/src/bootstrap/flags.rs b/src/bootstrap/flags.rs
index 8a38fedc6136d..42b949527e09d 100644
--- a/src/bootstrap/flags.rs
+++ b/src/bootstrap/flags.rs
@@ -278,9 +278,7 @@ Arguments:
         let src = matches.opt_str("src").map(PathBuf::from)
             .or_else(|| env::var_os("SRC").map(PathBuf::from))
             .unwrap_or(cwd.clone());
-        let paths = matches.free[1..].iter().map(|p| {
-            cwd.join(p).strip_prefix(&src).expect("paths passed to be inside checkout").into()
-        }).collect::<Vec<PathBuf>>();
+        let paths = matches.free[1..].iter().map(|p| p.into()).collect::<Vec<PathBuf>>();
 
         let cfg_file = matches.opt_str("config").map(PathBuf::from).or_else(|| {
             if fs::metadata("config.toml").is_ok() {
@@ -380,9 +378,7 @@ Arguments:
             cmd,
             incremental: matches.opt_present("incremental"),
             exclude: split(matches.opt_strs("exclude"))
-                .into_iter().map(|p| {
-                    cwd.join(p).strip_prefix(&src).expect("paths to be inside checkout").into()
-                }).collect::<Vec<_>>(),
+                .into_iter().map(|p| p.into()).collect::<Vec<_>>(),
             src,
         }
     }

From c788433b15a81935abcb84e9644d04422bf84a48 Mon Sep 17 00:00:00 2001
From: kennytm <kennytm@gmail.com>
Date: Fri, 16 Feb 2018 14:27:45 +0800
Subject: [PATCH 3/3] Fix panic when `x.py` is called without any arguments.

---
 src/bootstrap/builder.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 7345b284dc70a..66a1c97246200 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -385,8 +385,10 @@ impl<'a> Builder<'a> {
             Subcommand::Clean { .. } => panic!(),
         };
 
-        if paths[0] == Path::new("nonexistent/path/to/trigger/cargo/metadata") {
-            return;
+        if let Some(path) = paths.get(0) {
+            if path == Path::new("nonexistent/path/to/trigger/cargo/metadata") {
+                return;
+            }
         }
 
         let builder = Builder {