Auto merge of #139012 - Zalathar:rollup-qgt5yfo, r=Zalathar

Rollup of 10 pull requests

Successful merges:

 - #130883 (Add environment variable query)
 - #138624 (Add mipsel maintainer)
 - #138672 (Avoiding calling queries when collecting active queries)
 - #138935 (Update wg-prio triagebot config)
 - #138946 (Un-bury chapters from the chapter list in rustc book)
 - #138964 (Implement lint against using Interner and InferCtxtLike in random compiler crates)
 - #138977 (Don't deaggregate InvocationParent just to reaggregate it again)
 - #138980 (Collect items referenced from var_debug_info)
 - #138985 (Use the correct binder scope for elided lifetimes in assoc consts)
 - #138987 (Always emit `native-static-libs` note, even if it is empty)

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

2 files changed, 50 insertions, 22 deletions

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index 8be7ba7455e..2440f0639c8 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -1,5 +1,5 @@
 use std::any::Any;
-use std::ffi::OsString;
+use std::ffi::{OsStr, OsString};
 use std::io::{self, BufWriter, Write};
 use std::path::{Path, PathBuf};
 use std::sync::{Arc, LazyLock, OnceLock};
@@ -361,6 +361,31 @@ fn early_lint_checks(tcx: TyCtxt<'_>, (): ()) {
     )
 }
 
+fn env_var_os<'tcx>(tcx: TyCtxt<'tcx>, key: &'tcx OsStr) -> Option<&'tcx OsStr> {
+    let value = env::var_os(key);
+
+    let value_tcx = value.as_ref().map(|value| {
+        let encoded_bytes = tcx.arena.alloc_slice(value.as_encoded_bytes());
+        debug_assert_eq!(value.as_encoded_bytes(), encoded_bytes);
+        // SAFETY: The bytes came from `as_encoded_bytes`, and we assume that
+        // `alloc_slice` is implemented correctly, and passes the same bytes
+        // back (debug asserted above).
+        unsafe { OsStr::from_encoded_bytes_unchecked(encoded_bytes) }
+    });
+
+    // Also add the variable to Cargo's dependency tracking
+    //
+    // NOTE: This only works for passes run before `write_dep_info`. See that
+    // for extension points for configuring environment variables to be
+    // properly change-tracked.
+    tcx.sess.psess.env_depinfo.borrow_mut().insert((
+        Symbol::intern(&key.to_string_lossy()),
+        value.as_ref().and_then(|value| value.to_str()).map(|value| Symbol::intern(&value)),
+    ));
+
+    value_tcx
+}
+
 // Returns all the paths that correspond to generated files.
 fn generated_output_paths(
     tcx: TyCtxt<'_>,
@@ -725,6 +750,7 @@ pub static DEFAULT_QUERY_PROVIDERS: LazyLock<Providers> = LazyLock::new(|| {
         |tcx, _| tcx.arena.alloc_from_iter(tcx.resolutions(()).stripped_cfg_items.steal());
     providers.resolutions = |tcx, ()| tcx.resolver_for_lowering_raw(()).1;
     providers.early_lint_checks = early_lint_checks;
+    providers.env_var_os = env_var_os;
     limits::provide(providers);
     proc_macro_decls::provide(providers);
     rustc_const_eval::provide(providers);
diff --git a/compiler/rustc_interface/src/util.rs b/compiler/rustc_interface/src/util.rs
index 333786f0ca3..83d80938b4e 100644
--- a/compiler/rustc_interface/src/util.rs
+++ b/compiler/rustc_interface/src/util.rs
@@ -18,7 +18,7 @@ use rustc_session::{EarlyDiagCtxt, Session, filesearch};
 use rustc_span::edit_distance::find_best_match_for_name;
 use rustc_span::edition::Edition;
 use rustc_span::source_map::SourceMapInputs;
-use rustc_span::{Symbol, sym};
+use rustc_span::{SessionGlobals, Symbol, sym};
 use rustc_target::spec::Target;
 use tracing::info;
 
@@ -188,26 +188,11 @@ pub(crate) fn run_in_thread_pool_with_globals<F: FnOnce(CurrentGcx) -> R + Send,
             // On deadlock, creates a new thread and forwards information in thread
             // locals to it. The new thread runs the deadlock handler.
 
-            // Get a `GlobalCtxt` reference from `CurrentGcx` as we cannot rely on having a
-            // `TyCtxt` TLS reference here.
-            let query_map = current_gcx2.access(|gcx| {
-                tls::enter_context(&tls::ImplicitCtxt::new(gcx), || {
-                    tls::with(|tcx| {
-                        match QueryCtxt::new(tcx).collect_active_jobs() {
-                            Ok(query_map) => query_map,
-                            Err(_) => {
-                                // There was an unexpected error collecting all active jobs, which we need
-                                // to find cycles to break.
-                                // We want to avoid panicking in the deadlock handler, so we abort instead.
-                                eprintln!("internal compiler error: failed to get query map in deadlock handler, aborting process");
-                                process::abort();
-                            }
-                        }
-                    })
-                })
-            });
-            let query_map = FromDyn::from(query_map);
+            let current_gcx2 = current_gcx2.clone();
             let registry = rayon_core::Registry::current();
+            let session_globals = rustc_span::with_session_globals(|session_globals| {
+                session_globals as *const SessionGlobals as usize
+            });
             thread::Builder::new()
                 .name("rustc query cycle handler".to_string())
                 .spawn(move || {
@@ -217,7 +202,24 @@ pub(crate) fn run_in_thread_pool_with_globals<F: FnOnce(CurrentGcx) -> R + Send,
                         // otherwise the compiler could just hang,
                         process::abort();
                     });
-                    break_query_cycles(query_map.into_inner(), &registry);
+
+                    // Get a `GlobalCtxt` reference from `CurrentGcx` as we cannot rely on having a
+                    // `TyCtxt` TLS reference here.
+                    current_gcx2.access(|gcx| {
+                        tls::enter_context(&tls::ImplicitCtxt::new(gcx), || {
+                            tls::with(|tcx| {
+                                // Accessing session globals is sound as they outlive `GlobalCtxt`.
+                                // They are needed to hash query keys containing spans or symbols.
+                                let query_map = rustc_span::set_session_globals_then(unsafe { &*(session_globals as *const SessionGlobals) }, || {
+                                    // Ensure there was no errors collecting all active jobs.
+                                    // We need the complete map to ensure we find a cycle to break.
+                                    QueryCtxt::new(tcx).collect_active_jobs().ok().expect("failed to collect active queries in deadlock handler")
+                                });
+                                break_query_cycles(query_map, &registry);
+                            })
+                        })
+                    });
+
                     on_panic.disable();
                 })
                 .unwrap();