Auto merge of #111342 - Dylan-DPC:rollup-b5p6wzy, r=Dylan-DPC

Rollup of 7 pull requests

Successful merges:

 - #110297 (Make `(try_)subst_and_normalize_erasing_regions` take `EarlyBinder`)
 - #110827 (Fix lifetime suggestion for type aliases with objects in them)
 - #111022 (Use smaller ints for bitflags)
 - #111056 (Fix some suggestions where a `Box<T>` is expected.)
 - #111262 (Further normalize msvc-non-utf8-ouput)
 - #111265 (Make generics_of has_self on RPITITs delegate to the opaque)
 - #111323 (Give a more helpful error when running the rustc shim directly)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

3 files changed, 18 insertions, 5 deletions

diff --git a/src/bootstrap/bin/rustc.rs b/src/bootstrap/bin/rustc.rs
index dd86634b47c..e87125a49a6 100644
--- a/src/bootstrap/bin/rustc.rs
+++ b/src/bootstrap/bin/rustc.rs
@@ -19,7 +19,7 @@ include!("../dylib_util.rs");
 
 use std::env;
 use std::path::PathBuf;
-use std::process::{Child, Command};
+use std::process::{exit, Child, Command};
 use std::str::FromStr;
 use std::time::Instant;
 
@@ -47,7 +47,12 @@ fn main() {
     } else {
         ("RUSTC_REAL", "RUSTC_LIBDIR")
     };
-    let stage = env::var("RUSTC_STAGE").expect("RUSTC_STAGE was not set");
+    let stage = env::var("RUSTC_STAGE").unwrap_or_else(|_| {
+        // Don't panic here; it's reasonable to try and run these shims directly. Give a helpful error instead.
+        eprintln!("rustc shim: fatal: RUSTC_STAGE was not set");
+        eprintln!("rustc shim: note: use `x.py build -vvv` to see all environment variables set by bootstrap");
+        exit(101);
+    });
     let sysroot = env::var_os("RUSTC_SYSROOT").expect("RUSTC_SYSROOT was not set");
     let on_fail = env::var_os("RUSTC_ON_FAIL").map(Command::new);
 
diff --git a/src/bootstrap/bin/rustdoc.rs b/src/bootstrap/bin/rustdoc.rs
index 23828f4758d..d2b85f7a629 100644
--- a/src/bootstrap/bin/rustdoc.rs
+++ b/src/bootstrap/bin/rustdoc.rs
@@ -5,13 +5,18 @@
 use std::env;
 use std::ffi::OsString;
 use std::path::PathBuf;
-use std::process::Command;
+use std::process::{exit, Command};
 
 include!("../dylib_util.rs");
 
 fn main() {
     let args = env::args_os().skip(1).collect::<Vec<_>>();
-    let stage = env::var("RUSTC_STAGE").expect("RUSTC_STAGE was not set");
+    let stage = env::var("RUSTC_STAGE").unwrap_or_else(|_| {
+        // Don't panic here; it's reasonable to try and run these shims directly. Give a helpful error instead.
+        eprintln!("rustc shim: fatal: RUSTC_STAGE was not set");
+        eprintln!("rustc shim: note: use `x.py build -vvv` to see all environment variables set by bootstrap");
+        exit(101);
+    });
     let rustdoc = env::var_os("RUSTDOC_REAL").expect("RUSTDOC_REAL was not set");
     let libdir = env::var_os("RUSTDOC_LIBDIR").expect("RUSTDOC_LIBDIR was not set");
     let sysroot = env::var_os("RUSTC_SYSROOT").expect("RUSTC_SYSROOT was not set");
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
index 4c4c003ca46..67b7d3691dc 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
@@ -385,6 +385,9 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
             Node::Expr(parent_expr) => {
                 if let Some((callee_def_id, call_substs, recv, call_args)) = get_callee_substs_and_args(cx, parent_expr)
                 {
+                    // FIXME: the `subst_identity()` below seems incorrect, since we eventually
+                    // call `tcx.try_subst_and_normalize_erasing_regions` further down
+                    // (i.e., we are explicitly not in the identity context).
                     let fn_sig = cx.tcx.fn_sig(callee_def_id).subst_identity().skip_binder();
                     if let Some(arg_index) = recv.into_iter().chain(call_args).position(|arg| arg.hir_id == expr.hir_id)
                         && let Some(param_ty) = fn_sig.inputs().get(arg_index)
@@ -435,7 +438,7 @@ fn can_change_type<'a>(cx: &LateContext<'a>, mut expr: &'a Expr<'a>, mut ty: Ty<
                         let output_ty = fn_sig.output();
                         if output_ty.contains(*param_ty) {
                             if let Ok(new_ty)  = cx.tcx.try_subst_and_normalize_erasing_regions(
-                                new_subst, cx.param_env, output_ty) {
+                                new_subst, cx.param_env, EarlyBinder(output_ty)) {
                                 expr = parent_expr;
                                 ty = new_ty;
                                 continue;