Rollup of 4 pull requests

compiler/rustc_borrowck/src/type_check/opaque_types.rs

@@ -25,8 +25,8 @@ pub(super) fn take_opaques_and_register_member_constraints<'tcx>(
     let opaque_types = infcx
         .take_opaque_types()
         .into_iter()
-        .map(|(opaque_type_key, decl)| {
-            let hidden_type = infcx.resolve_vars_if_possible(decl.hidden_type);
+        .map(|(opaque_type_key, hidden_type)| {
+            let hidden_type = infcx.resolve_vars_if_possible(hidden_type);
             register_member_constraints(
                 typeck,
                 &mut member_constraints,

compiler/rustc_hir_analysis/src/check/check.rs

@@ -436,9 +436,9 @@ fn check_opaque_meets_bounds<'tcx>(
     } else {
         // Check that any hidden types found during wf checking match the hidden types that `type_of` sees.
         for (mut key, mut ty) in infcx.take_opaque_types() {
-            ty.hidden_type.ty = infcx.resolve_vars_if_possible(ty.hidden_type.ty);
+            ty.ty = infcx.resolve_vars_if_possible(ty.ty);
             key = infcx.resolve_vars_if_possible(key);
-            sanity_check_found_hidden_type(tcx, key, ty.hidden_type)?;
+            sanity_check_found_hidden_type(tcx, key, ty)?;
         }
         Ok(())
     }
@@ -1873,7 +1873,7 @@ pub(super) fn check_coroutine_obligations(
         // Check that any hidden types found when checking these stalled coroutine obligations
         // are valid.
         for (key, ty) in infcx.take_opaque_types() {
-            let hidden_type = infcx.resolve_vars_if_possible(ty.hidden_type);
+            let hidden_type = infcx.resolve_vars_if_possible(ty);
             let key = infcx.resolve_vars_if_possible(key);
             sanity_check_found_hidden_type(tcx, key, hidden_type)?;
         }

compiler/rustc_hir_typeck/src/writeback.rs

@@ -562,9 +562,9 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
         // types or by using this function at the end of writeback and running it as a
         // fixpoint.
         let opaque_types = self.fcx.infcx.clone_opaque_types();
-        for (opaque_type_key, decl) in opaque_types {
-            let hidden_type = self.resolve(decl.hidden_type, &decl.hidden_type.span);
-            let opaque_type_key = self.resolve(opaque_type_key, &decl.hidden_type.span);
+        for (opaque_type_key, hidden_type) in opaque_types {
+            let hidden_type = self.resolve(hidden_type, &hidden_type.span);
+            let opaque_type_key = self.resolve(opaque_type_key, &hidden_type.span);
 
             if !self.fcx.next_trait_solver() {
                 if let ty::Alias(ty::Opaque, alias_ty) = hidden_type.ty.kind()

compiler/rustc_infer/src/infer/canonical/query_response.rs

@@ -155,12 +155,12 @@ impl<'tcx> InferCtxt<'tcx> {
             .opaque_type_storage
             .opaque_types
             .iter()
-            .map(|(k, v)| (*k, v.hidden_type.ty))
+            .map(|(k, v)| (*k, v.ty))
             .collect()
     }
 
     fn take_opaque_types_for_query_response(&self) -> Vec<(ty::OpaqueTypeKey<'tcx>, Ty<'tcx>)> {
-        self.take_opaque_types().into_iter().map(|(k, v)| (k, v.hidden_type.ty)).collect()
+        self.take_opaque_types().into_iter().map(|(k, v)| (k, v.ty)).collect()
     }
 
     /// Given the (canonicalized) result to a canonical query,

compiler/rustc_infer/src/infer/mod.rs

@@ -234,7 +234,7 @@ impl<'tcx> InferCtxtInner<'tcx> {
     pub fn iter_opaque_types(
         &self,
     ) -> impl Iterator<Item = (ty::OpaqueTypeKey<'tcx>, ty::OpaqueHiddenType<'tcx>)> + '_ {
-        self.opaque_type_storage.opaque_types.iter().map(|(&k, v)| (k, v.hidden_type))
+        self.opaque_type_storage.opaque_types.iter().map(|(&k, &v)| (k, v))
     }
 }
 

compiler/rustc_infer/src/infer/opaque_types/mod.rs

@@ -19,20 +19,9 @@ use crate::traits::{self, Obligation, PredicateObligations};
 
 mod table;
 
-pub(crate) type OpaqueTypeMap<'tcx> = FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueTypeDecl<'tcx>>;
+pub(crate) type OpaqueTypeMap<'tcx> = FxIndexMap<OpaqueTypeKey<'tcx>, OpaqueHiddenType<'tcx>>;
 pub(crate) use table::{OpaqueTypeStorage, OpaqueTypeTable};
 
-/// Information about the opaque types whose values we
-/// are inferring in this function (these are the `impl Trait` that
-/// appear in the return type).
-#[derive(Clone, Debug)]
-pub struct OpaqueTypeDecl<'tcx> {
-    /// The hidden types that have been inferred for this opaque type.
-    /// There can be multiple, but they are all `lub`ed together at the end
-    /// to obtain the canonical hidden type.
-    pub hidden_type: OpaqueHiddenType<'tcx>,
-}
-
 impl<'tcx> InferCtxt<'tcx> {
     /// This is a backwards compatibility hack to prevent breaking changes from
     /// lazy TAIT around RPIT handling.

compiler/rustc_infer/src/infer/opaque_types/table.rs

@@ -3,23 +3,27 @@ use rustc_middle::bug;
 use rustc_middle::ty::{self, OpaqueHiddenType, OpaqueTypeKey, Ty};
 use tracing::instrument;
 
-use super::{OpaqueTypeDecl, OpaqueTypeMap};
+use super::OpaqueTypeMap;
 use crate::infer::snapshot::undo_log::{InferCtxtUndoLogs, UndoLog};
 
 #[derive(Default, Debug, Clone)]
 pub(crate) struct OpaqueTypeStorage<'tcx> {
     /// Opaque types found in explicit return types and their
     /// associated fresh inference variable. Writeback resolves these
     /// variables to get the concrete type, which can be used to
-    /// 'de-opaque' OpaqueTypeDecl, after typeck is done with all functions.
+    /// 'de-opaque' OpaqueHiddenType, after typeck is done with all functions.
     pub opaque_types: OpaqueTypeMap<'tcx>,
 }
 
 impl<'tcx> OpaqueTypeStorage<'tcx> {
     #[instrument(level = "debug")]
-    pub(crate) fn remove(&mut self, key: OpaqueTypeKey<'tcx>, idx: Option<OpaqueHiddenType<'tcx>>) {
-        if let Some(idx) = idx {
-            self.opaque_types.get_mut(&key).unwrap().hidden_type = idx;
+    pub(crate) fn remove(
+        &mut self,
+        key: OpaqueTypeKey<'tcx>,
+        prev: Option<OpaqueHiddenType<'tcx>>,
+    ) {
+        if let Some(prev) = prev {
+            *self.opaque_types.get_mut(&key).unwrap() = prev;
         } else {
             // FIXME(#120456) - is `swap_remove` correct?
             match self.opaque_types.swap_remove(&key) {
@@ -59,13 +63,12 @@ impl<'a, 'tcx> OpaqueTypeTable<'a, 'tcx> {
         key: OpaqueTypeKey<'tcx>,
         hidden_type: OpaqueHiddenType<'tcx>,
     ) -> Option<Ty<'tcx>> {
-        if let Some(decl) = self.storage.opaque_types.get_mut(&key) {
-            let prev = std::mem::replace(&mut decl.hidden_type, hidden_type);
+        if let Some(entry) = self.storage.opaque_types.get_mut(&key) {
+            let prev = std::mem::replace(entry, hidden_type);
             self.undo_log.push(UndoLog::OpaqueTypes(key, Some(prev)));
             return Some(prev.ty);
         }
-        let decl = OpaqueTypeDecl { hidden_type };
-        self.storage.opaque_types.insert(key, decl);
+        self.storage.opaque_types.insert(key, hidden_type);
         self.undo_log.push(UndoLog::OpaqueTypes(key, None));
         None
     }

compiler/rustc_lint/src/impl_trait_overcaptures.rs

@@ -99,7 +99,7 @@ declare_lint! {
     /// To fix this, remove the `use<'a>`, since the lifetime is already captured
     /// since it is in scope.
     pub IMPL_TRAIT_REDUNDANT_CAPTURES,
-    Warn,
+    Allow,
     "redundant precise-capturing `use<...>` syntax on an `impl Trait`",
 }
 

compiler/rustc_middle/src/mir/pretty.rs

@@ -1555,16 +1555,22 @@ pub fn write_allocations<'tcx>(
                 write!(w, " (vtable: impl {dyn_ty} for {ty})")?
             }
             Some(GlobalAlloc::Static(did)) if !tcx.is_foreign_item(did) => {
-                match tcx.eval_static_initializer(did) {
-                    Ok(alloc) => {
-                        write!(w, " (static: {}, ", tcx.def_path_str(did))?;
-                        write_allocation_track_relocs(w, alloc)?;
+                write!(w, " (static: {}", tcx.def_path_str(did))?;
+                if body.phase <= MirPhase::Runtime(RuntimePhase::PostCleanup)
+                    && tcx.hir().body_const_context(body.source.def_id()).is_some()
+                {
+                    // Statics may be cyclic and evaluating them too early
+                    // in the MIR pipeline may cause cycle errors even though
+                    // normal compilation is fine.
+                    write!(w, ")")?;
+                } else {
+                    match tcx.eval_static_initializer(did) {
+                        Ok(alloc) => {
+                            write!(w, ", ")?;
+                            write_allocation_track_relocs(w, alloc)?;
+                        }
+                        Err(_) => write!(w, ", error during initializer evaluation)")?,
                     }
-                    Err(_) => write!(
-                        w,
-                        " (static: {}, error during initializer evaluation)",
-                        tcx.def_path_str(did)
-                    )?,
                 }
             }
             Some(GlobalAlloc::Static(did)) => {

library/std/src/rt.rs

@@ -67,7 +67,7 @@ macro_rules! rtunwrap {
     };
 }
 
-fn handle_rt_panic(e: Box<dyn Any + Send>) {
+fn handle_rt_panic<T>(e: Box<dyn Any + Send>) -> T {
     mem::forget(e);
     rtabort!("initialization or cleanup bug");
 }
@@ -157,7 +157,7 @@ fn lang_start_internal(
     argc: isize,
     argv: *const *const u8,
     sigpipe: u8,
-) -> Result<isize, !> {
+) -> isize {
     // Guard against the code called by this function from unwinding outside of the Rust-controlled
     // code, which is UB. This is a requirement imposed by a combination of how the
     // `#[lang="start"]` attribute is implemented as well as by the implementation of the panicking
@@ -168,19 +168,33 @@ fn lang_start_internal(
     // panic is a std implementation bug. A quite likely one too, as there isn't any way to
     // prevent std from accidentally introducing a panic to these functions. Another is from
     // user code from `main` or, more nefariously, as described in e.g. issue #86030.
-    // SAFETY: Only called once during runtime initialization.
-    panic::catch_unwind(move || unsafe { init(argc, argv, sigpipe) })
-        .unwrap_or_else(handle_rt_panic);
-    let ret_code = panic::catch_unwind(move || panic::catch_unwind(main).unwrap_or(101) as isize)
-        .map_err(move |e| {
-            mem::forget(e);
-            rtabort!("drop of the panic payload panicked");
+    //
+    // We use `catch_unwind` with `handle_rt_panic` instead of `abort_unwind` to make the error in
+    // case of a panic a bit nicer.
+    panic::catch_unwind(move || {
+        // SAFETY: Only called once during runtime initialization.
+        unsafe { init(argc, argv, sigpipe) };
+
+        let ret_code = panic::catch_unwind(main).unwrap_or_else(move |payload| {
+            // Carefully dispose of the panic payload.
+            let payload = panic::AssertUnwindSafe(payload);
+            panic::catch_unwind(move || drop({ payload }.0)).unwrap_or_else(move |e| {
+                mem::forget(e); // do *not* drop the 2nd payload
+                rtabort!("drop of the panic payload panicked");
+            });
+            // Return error code for panicking programs.
+            101
         });
-    panic::catch_unwind(cleanup).unwrap_or_else(handle_rt_panic);
-    // Guard against multiple threads calling `libc::exit` concurrently.
-    // See the documentation for `unique_thread_exit` for more information.
-    panic::catch_unwind(crate::sys::exit_guard::unique_thread_exit).unwrap_or_else(handle_rt_panic);
-    ret_code
+        let ret_code = ret_code as isize;
+
+        cleanup();
+        // Guard against multiple threads calling `libc::exit` concurrently.
+        // See the documentation for `unique_thread_exit` for more information.
+        crate::sys::exit_guard::unique_thread_exit();
+
+        ret_code
+    })
+    .unwrap_or_else(handle_rt_panic)
 }
 
 #[cfg(not(any(test, doctest)))]
@@ -191,11 +205,10 @@ fn lang_start<T: crate::process::Termination + 'static>(
     argv: *const *const u8,
     sigpipe: u8,
 ) -> isize {
-    let Ok(v) = lang_start_internal(
+    lang_start_internal(
         &move || crate::sys::backtrace::__rust_begin_short_backtrace(main).report().to_i32(),
         argc,
         argv,
         sigpipe,
-    );
-    v
+    )
 }

src/tools/miri/tests/fail/tail_calls/cc-mismatch.stderr

@@ -15,9 +15,9 @@ LL |     extern "rust-call" fn call_once(self, args: Args) -> Self::Output;
    = note: inside `std::panicking::r#try::<i32, &dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe>` at RUSTLIB/std/src/panicking.rs:LL:CC
    = note: inside `std::panic::catch_unwind::<&dyn std::ops::Fn() -> i32 + std::marker::Sync + std::panic::RefUnwindSafe, i32>` at RUSTLIB/std/src/panic.rs:LL:CC
    = note: inside closure at RUSTLIB/std/src/rt.rs:LL:CC
-   = note: inside `std::panicking::r#try::do_call::<{closure@std::rt::lang_start_internal::{closure#1}}, isize>` at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::panicking::r#try::<isize, {closure@std::rt::lang_start_internal::{closure#1}}>` at RUSTLIB/std/src/panicking.rs:LL:CC
-   = note: inside `std::panic::catch_unwind::<{closure@std::rt::lang_start_internal::{closure#1}}, isize>` at RUSTLIB/std/src/panic.rs:LL:CC
+   = note: inside `std::panicking::r#try::do_call::<{closure@std::rt::lang_start_internal::{closure#0}}, isize>` at RUSTLIB/std/src/panicking.rs:LL:CC
+   = note: inside `std::panicking::r#try::<isize, {closure@std::rt::lang_start_internal::{closure#0}}>` at RUSTLIB/std/src/panicking.rs:LL:CC
+   = note: inside `std::panic::catch_unwind::<{closure@std::rt::lang_start_internal::{closure#0}}, isize>` at RUSTLIB/std/src/panic.rs:LL:CC
    = note: inside `std::rt::lang_start_internal` at RUSTLIB/std/src/rt.rs:LL:CC
    = note: inside `std::rt::lang_start::<()>` at RUSTLIB/std/src/rt.rs:LL:CC
 

src/tools/miri/tests/pass/backtrace/backtrace-api-v1.stderr

@@ -10,7 +10,7 @@ RUSTLIB/core/src/ops/function.rs:LL:CC (std::ops::function::impls::call_once)
 RUSTLIB/std/src/panicking.rs:LL:CC (std::panicking::r#try::do_call)
 RUSTLIB/std/src/panicking.rs:LL:CC (std::panicking::r#try)
 RUSTLIB/std/src/panic.rs:LL:CC (std::panic::catch_unwind)
-RUSTLIB/std/src/rt.rs:LL:CC (std::rt::lang_start_internal::{closure#1})
+RUSTLIB/std/src/rt.rs:LL:CC (std::rt::lang_start_internal::{closure#0})
 RUSTLIB/std/src/panicking.rs:LL:CC (std::panicking::r#try::do_call)
 RUSTLIB/std/src/panicking.rs:LL:CC (std::panicking::r#try)
 RUSTLIB/std/src/panic.rs:LL:CC (std::panic::catch_unwind)

src/tools/miri/tests/pass/backtrace/backtrace-global-alloc.stderr

@@ -14,7 +14,7 @@
  at RUSTLIB/std/src/panicking.rs:LL:CC
    7: std::panic::catch_unwind
  at RUSTLIB/std/src/panic.rs:LL:CC
-   8: std::rt::lang_start_internal::{closure#1}
+   8: std::rt::lang_start_internal::{closure#0}
  at RUSTLIB/std/src/rt.rs:LL:CC
    9: std::panicking::r#try::do_call
  at RUSTLIB/std/src/panicking.rs:LL:CC

src/tools/miri/tests/pass/backtrace/backtrace-std.stderr

@@ -22,7 +22,7 @@
  at RUSTLIB/std/src/panicking.rs:LL:CC
   11: std::panic::catch_unwind
  at RUSTLIB/std/src/panic.rs:LL:CC
-  12: std::rt::lang_start_internal::{closure#1}
+  12: std::rt::lang_start_internal::{closure#0}
  at RUSTLIB/std/src/rt.rs:LL:CC
   13: std::panicking::r#try::do_call
  at RUSTLIB/std/src/panicking.rs:LL:CC

tests/mir-opt/building/dump_mir_cycle.rs

@@ -0,0 +1,19 @@
+#[derive(Debug)]
+pub struct Thing {
+    pub next: &'static Thing,
+}
+
+pub static THING: Thing = Thing { next: &THING };
+// CHECK: alloc{{.+}} (static: THING)
+
+const fn thing() -> &'static Thing {
+    &MUTUALLY_RECURSIVE
+}
+
+pub static MUTUALLY_RECURSIVE: Thing = Thing { next: thing() };
+// CHECK: alloc{{.+}} (static: MUTUALLY_RECURSIVE)
+
+fn main() {
+    // Generate optimized MIR for the const fn, too.
+    thing();
+}

tests/mir-opt/const_promotion_extern_static.BAR-promoted[0].SimplifyCfg-pre-optimizations.after.mir

@@ -15,6 +15,4 @@ const BAR::promoted[0]: &[&i32; 1] = {
     }
 }
 
-ALLOC0 (static: Y, size: 4, align: 4) {
-    2a 00 00 00                                     │ *...
-}
+ALLOC0 (static: Y)

tests/mir-opt/const_promotion_extern_static.BAR.PromoteTemps.diff

@@ -38,9 +38,7 @@
       bb2 (cleanup): {
           resume;
       }
-- }
-- 
-- ALLOC0 (static: Y, size: 4, align: 4) {
--     2a 00 00 00                                     │ *...
   }
+- 
+- ALLOC0 (static: Y)
 

tests/ui/impl-trait/precise-capturing/redundant.rs

@@ -1,24 +1,24 @@
 //@ edition: 2024
-//@ check-pass
 
 #![feature(precise_capturing_in_traits)]
+#![deny(impl_trait_redundant_captures)]
 
 fn hello<'a>() -> impl Sized + use<'a> {}
-//~^ WARN all possible in-scope parameters are already captured
+//~^ ERROR all possible in-scope parameters are already captured
 
 struct Inherent;
 impl Inherent {
     fn inherent(&self) -> impl Sized + use<'_> {}
-    //~^ WARN all possible in-scope parameters are already captured
+    //~^ ERROR all possible in-scope parameters are already captured
 }
 
 trait Test<'a> {
     fn in_trait() -> impl Sized + use<'a, Self>;
-    //~^ WARN all possible in-scope parameters are already captured
+    //~^ ERROR all possible in-scope parameters are already captured
 }
 impl<'a> Test<'a> for () {
     fn in_trait() -> impl Sized + use<'a> {}
-    //~^ WARN all possible in-scope parameters are already captured
+    //~^ ERROR all possible in-scope parameters are already captured
 }
 
 fn main() {}