Auto merge of rust-lang#124688 - compiler-errors:rollup-qhi9pyn, r=compiler-errors

Rollup of 8 pull requests

Successful merges:

 - rust-lang#124293 (Let miri and const eval execute intrinsics' fallback bodies)
 - rust-lang#124418 (Use a proof tree visitor to refine the `Obligation` for error reporting in new solver)
 - rust-lang#124480 (Change `SIGPIPE` ui from `#[unix_sigpipe = "..."]` to `-Zon-broken-pipe=...`)
 - rust-lang#124648 (Trim crate graph)
 - rust-lang#124656 (release notes 1.78: add link to interior-mut breaking change)
 - rust-lang#124658 (Migrate `run-make/doctests-keep-binaries` to new rmake.rs format)
 - rust-lang#124681 (zkvm: fix run_tests)
 - rust-lang#124687 (Make `Bounds.clauses` private)

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

Author: bors

Cargo.lock

@@ -3824,7 +3824,6 @@ dependencies = [
  "rustc_session",
  "rustc_smir",
  "rustc_span",
- "rustc_symbol_mangling",
  "rustc_target",
  "rustc_trait_selection",
  "rustc_ty_utils",
@@ -4008,7 +4007,6 @@ dependencies = [
  "rustc_data_structures",
  "rustc_errors",
  "rustc_fluent_macro",
- "rustc_graphviz",
  "rustc_hir",
  "rustc_hir_analysis",
  "rustc_hir_pretty",
@@ -4468,7 +4466,6 @@ dependencies = [
  "rustc_errors",
  "rustc_fluent_macro",
  "rustc_hir",
- "rustc_hir_analysis",
  "rustc_macros",
  "rustc_middle",
  "rustc_session",
@@ -4515,7 +4512,6 @@ dependencies = [
  "rustc_session",
  "rustc_span",
  "rustc_target",
- "rustc_type_ir",
  "smallvec",
  "thin-vec",
  "tracing",

RELEASES.md

@@ -102,6 +102,10 @@ Compatibility Notes
 - [Change equality of higher ranked types to not rely on subtyping](https://github.com/rust-lang/rust/pull/118247)
 - [When called, additionally check bounds on normalized function return type](https://github.com/rust-lang/rust/pull/118882)
 - [Expand coverage for `arithmetic_overflow` lint](https://github.com/rust-lang/rust/pull/119432/)
+- [Fix detection of potential interior mutability in `const` initializers](https://github.com/rust-lang/rust/issues/121250)
+  This code was accidentally accepted. The fix can break generic code that borrows a value of unknown type,
+  as there is currently no way to declare "this type has no interior mutability". In the future, stabilizing
+  the [`Freeze` trait](https://github.com/rust-lang/rust/issues/121675) will allow proper support for such code.
 
 <a id="1.78.0-Internal-Changes"></a>
 

compiler/rustc/src/main.rs

@@ -1,5 +1,3 @@
-#![feature(unix_sigpipe)]
-
 // A note about jemalloc: rustc uses jemalloc when built for CI and
 // distribution. The obvious way to do this is with the `#[global_allocator]`
 // mechanism. However, for complicated reasons (see
@@ -34,7 +32,6 @@
 // https://github.com/rust-lang/rust/commit/b90cfc887c31c3e7a9e6d462e2464db1fe506175#diff-43914724af6e464c1da2171e4a9b6c7e607d5bc1203fa95c0ab85be4122605ef
 // for an example of how to do so.
 
-#[unix_sigpipe = "sig_dfl"]
 fn main() {
     // See the comment at the top of this file for an explanation of this.
     #[cfg(feature = "jemalloc-sys")]

compiler/rustc_builtin_macros/src/format.rs

@@ -307,7 +307,7 @@ fn make_format_args(
         return ExpandResult::Ready(Err(guar));
     }
 
-    let to_span = |inner_span: rustc_parse_format::InnerSpan| {
+    let to_span = |inner_span: parse::InnerSpan| {
         is_source_literal.then(|| {
             fmt_span.from_inner(InnerSpan { start: inner_span.start, end: inner_span.end })
         })
@@ -577,7 +577,7 @@ fn make_format_args(
 fn invalid_placeholder_type_error(
     ecx: &ExtCtxt<'_>,
     ty: &str,
-    ty_span: Option<rustc_parse_format::InnerSpan>,
+    ty_span: Option<parse::InnerSpan>,
     fmt_span: Span,
 ) {
     let sp = ty_span.map(|sp| fmt_span.from_inner(InnerSpan::new(sp.start, sp.end)));

compiler/rustc_const_eval/src/const_eval/dummy_machine.rs

@@ -105,7 +105,7 @@ impl<'mir, 'tcx: 'mir> interpret::Machine<'mir, 'tcx> for DummyMachine {
         _destination: &interpret::MPlaceTy<'tcx, Self::Provenance>,
         _target: Option<BasicBlock>,
         _unwind: UnwindAction,
-    ) -> interpret::InterpResult<'tcx> {
+    ) -> interpret::InterpResult<'tcx, Option<ty::Instance<'tcx>>> {
         unimplemented!()
     }
 

compiler/rustc_const_eval/src/const_eval/machine.rs

@@ -459,16 +459,26 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir,
         dest: &MPlaceTy<'tcx, Self::Provenance>,
         target: Option<mir::BasicBlock>,
         _unwind: mir::UnwindAction,
-    ) -> InterpResult<'tcx> {
+    ) -> InterpResult<'tcx, Option<ty::Instance<'tcx>>> {
         // Shared intrinsics.
         if ecx.emulate_intrinsic(instance, args, dest, target)? {
-            return Ok(());
+            return Ok(None);
         }
         let intrinsic_name = ecx.tcx.item_name(instance.def_id());
 
         // CTFE-specific intrinsics.
         let Some(ret) = target else {
-            throw_unsup_format!("intrinsic `{intrinsic_name}` is not supported at compile-time");
+            // Handle diverging intrinsics. We can't handle any of them (that are not already
+            // handled above), but check if there is a fallback body.
+            if ecx.tcx.intrinsic(instance.def_id()).unwrap().must_be_overridden {
+                throw_unsup_format!(
+                    "intrinsic `{intrinsic_name}` is not supported at compile-time"
+                );
+            }
+            return Ok(Some(ty::Instance {
+                def: ty::InstanceDef::Item(instance.def_id()),
+                args: instance.args,
+            }));
         };
         match intrinsic_name {
             sym::ptr_guaranteed_cmp => {
@@ -536,14 +546,21 @@ impl<'mir, 'tcx> interpret::Machine<'mir, 'tcx> for CompileTimeInterpreter<'mir,
             // not the optimization stage.)
             sym::is_val_statically_known => ecx.write_scalar(Scalar::from_bool(false), dest)?,
             _ => {
-                throw_unsup_format!(
-                    "intrinsic `{intrinsic_name}` is not supported at compile-time"
-                );
+                // We haven't handled the intrinsic, let's see if we can use a fallback body.
+                if ecx.tcx.intrinsic(instance.def_id()).unwrap().must_be_overridden {
+                    throw_unsup_format!(
+                        "intrinsic `{intrinsic_name}` is not supported at compile-time"
+                    );
+                }
+                return Ok(Some(ty::Instance {
+                    def: ty::InstanceDef::Item(instance.def_id()),
+                    args: instance.args,
+                }));
             }
         }
 
         ecx.go_to_block(ret);
-        Ok(())
+        Ok(None)
     }
 
     fn assert_panic(

compiler/rustc_const_eval/src/interpret/intrinsics.rs

@@ -414,7 +414,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 }
                 self.copy_op(&self.project_index(&input, index)?, dest)?;
             }
-            sym::likely | sym::unlikely | sym::black_box => {
+            sym::black_box => {
                 // These just return their argument
                 self.copy_op(&args[0], dest)?;
             }

compiler/rustc_const_eval/src/interpret/machine.rs

@@ -216,14 +216,17 @@ pub trait Machine<'mir, 'tcx: 'mir>: Sized {
 
     /// Directly process an intrinsic without pushing a stack frame. It is the hook's
     /// responsibility to advance the instruction pointer as appropriate.
+    ///
+    /// Returns `None` if the intrinsic was fully handled.
+    /// Otherwise, returns an `Instance` of the function that implements the intrinsic.
     fn call_intrinsic(
         ecx: &mut InterpCx<'mir, 'tcx, Self>,
         instance: ty::Instance<'tcx>,
         args: &[OpTy<'tcx, Self::Provenance>],
         destination: &MPlaceTy<'tcx, Self::Provenance>,
         target: Option<mir::BasicBlock>,
         unwind: mir::UnwindAction,
-    ) -> InterpResult<'tcx>;
+    ) -> InterpResult<'tcx, Option<ty::Instance<'tcx>>>;
 
     /// Called to evaluate `Assert` MIR terminators that trigger a panic.
     fn assert_panic(

compiler/rustc_const_eval/src/interpret/terminator.rs

@@ -539,14 +539,28 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             ty::InstanceDef::Intrinsic(def_id) => {
                 assert!(self.tcx.intrinsic(def_id).is_some());
                 // FIXME: Should `InPlace` arguments be reset to uninit?
-                M::call_intrinsic(
+                if let Some(fallback) = M::call_intrinsic(
                     self,
                     instance,
                     &self.copy_fn_args(args),
                     destination,
                     target,
                     unwind,
-                )
+                )? {
+                    assert!(!self.tcx.intrinsic(fallback.def_id()).unwrap().must_be_overridden);
+                    assert!(matches!(fallback.def, ty::InstanceDef::Item(_)));
+                    return self.eval_fn_call(
+                        FnVal::Instance(fallback),
+                        (caller_abi, caller_fn_abi),
+                        args,
+                        with_caller_location,
+                        destination,
+                        target,
+                        unwind,
+                    );
+                } else {
+                    Ok(())
+                }
             }
             ty::InstanceDef::VTableShim(..)
             | ty::InstanceDef::ReifyShim(..)

compiler/rustc_driver_impl/Cargo.toml

@@ -42,9 +42,8 @@ rustc_privacy = { path = "../rustc_privacy" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_resolve = { path = "../rustc_resolve" }
 rustc_session = { path = "../rustc_session" }
-rustc_smir ={ path = "../rustc_smir" }
+rustc_smir = { path = "../rustc_smir" }
 rustc_span = { path = "../rustc_span" }
-rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_ty_utils = { path = "../rustc_ty_utils" }