Rollup of 7 pull requests

compiler/rustc_codegen_cranelift/rust-toolchain.toml

@@ -1,4 +1,4 @@
 [toolchain]
-channel = "nightly-2026-09-08"
+channel = "nightly-2026-09-10"
 components = ["rust-src", "rustc-dev", "llvm-tools", "rustfmt"]
 profile = "minimal"

compiler/rustc_codegen_cranelift/src/common.rs

@@ -5,8 +5,9 @@ use rustc_index::IndexVec;
 use rustc_middle::ty::TypeFoldable;
 use rustc_middle::ty::layout::{
     self, FnAbiError, FnAbiOfHelpers, FnAbiRequest, LayoutError, LayoutOfHelpers,
+    codegen_handle_fn_abi_err,
 };
-use rustc_span::{Spanned, Symbol};
+use rustc_span::Symbol;
 use rustc_target::callconv::FnAbi;
 use rustc_target::spec::{Arch, HasTargetSpec, Target};
 
@@ -453,23 +454,7 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for FullyMonomorphizedLayoutCx<'tcx> {
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
-        if let FnAbiError::Layout(LayoutError::SizeOverflow(_) | LayoutError::InvalidSimd { .. }) =
-            err
-        {
-            self.0.sess.dcx().emit_fatal(Spanned { span, node: err })
-        } else {
-            match fn_abi_request {
-                FnAbiRequest::OfFnPtr { sig, extra_args } => {
-                    span_bug!(span, "`fn_abi_of_fn_ptr({sig}, {extra_args:?})` failed: {err:?}");
-                }
-                FnAbiRequest::OfInstance { instance, extra_args } => {
-                    span_bug!(
-                        span,
-                        "`fn_abi_of_instance({instance}, {extra_args:?})` failed: {err:?}"
-                    );
-                }
-            }
-        }
+        codegen_handle_fn_abi_err(self.0, err, span, fn_abi_request).raise_fatal()
     }
 }
 

compiler/rustc_codegen_gcc/src/context.rs

@@ -10,16 +10,15 @@ use rustc_data_structures::base_n::{ALPHANUMERIC_ONLY, ToBaseN};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_middle::mir::interpret::Allocation;
 use rustc_middle::mono::CodegenUnit;
-use rustc_middle::span_bug;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOf, FnAbiOfHelpers, FnAbiRequest, HasTyCtxt, HasTypingEnv, LayoutError,
-    LayoutOfHelpers,
+    LayoutOfHelpers, codegen_handle_fn_abi_err,
 };
 use rustc_middle::ty::{self, ExistentialTraitRef, Instance, Ty, TyCtxt};
 #[cfg(feature = "master")]
 use rustc_session::config::DebugInfo;
 use rustc_session::{PointerAuthSchema, Session};
-use rustc_span::{DUMMY_SP, Span, Symbol, respan};
+use rustc_span::{DUMMY_SP, Span, Symbol};
 use rustc_target::spec::{HasTargetSpec, HasX86AbiOpt, Target, TlsModel, X86Abi};
 
 #[cfg(feature = "master")]
@@ -562,23 +561,7 @@ impl<'gcc, 'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'gcc, 'tcx> {
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
-        if let FnAbiError::Layout(LayoutError::SizeOverflow(_) | LayoutError::InvalidSimd { .. }) =
-            err
-        {
-            self.tcx.dcx().emit_fatal(respan(span, err))
-        } else {
-            match fn_abi_request {
-                FnAbiRequest::OfFnPtr { sig, extra_args } => {
-                    span_bug!(span, "`fn_abi_of_fn_ptr({sig}, {extra_args:?})` failed: {err:?}");
-                }
-                FnAbiRequest::OfInstance { instance, extra_args } => {
-                    span_bug!(
-                        span,
-                        "`fn_abi_of_instance({instance}, {extra_args:?})` failed: {err:?}"
-                    );
-                }
-            }
-        }
+        codegen_handle_fn_abi_err(self.tcx, err, span, fn_abi_request).raise_fatal()
     }
 }
 

compiler/rustc_codegen_llvm/src/context.rs

@@ -14,18 +14,19 @@ use rustc_data_structures::base_n::{ALPHANUMERIC_ONLY, ToBaseN};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_hir::def_id::DefId;
+use rustc_middle::bug;
 use rustc_middle::mono::CodegenUnit;
 use rustc_middle::ty::layout::{
     FnAbiError, FnAbiOfHelpers, FnAbiRequest, HasTypingEnv, LayoutError, LayoutOfHelpers,
+    codegen_handle_fn_abi_err,
 };
 use rustc_middle::ty::{self, Instance, Ty, TyCtxt};
-use rustc_middle::{bug, span_bug};
 use rustc_sanitizers::ignorelist::{SanitizerIgnoreList, typename_for_ignore_list};
 use rustc_session::config::{
     BranchProtection, CFGuard, CFProtection, DebugInfo, FunctionReturn, PAuthKey, PacRet,
 };
 use rustc_session::{PointerAuthSchema, Session};
-use rustc_span::{DUMMY_SP, Span, Spanned, Symbol, sym};
+use rustc_span::{DUMMY_SP, Span, Symbol, sym};
 use rustc_structures::CrateType;
 use rustc_target::spec::{
     Arch, CfgAbi, Env, FramePointer, HasTargetSpec, Os, RelocModel, SmallDataThresholdSupport,
@@ -1316,21 +1317,6 @@ impl<'tcx> FnAbiOfHelpers<'tcx> for CodegenCx<'_, 'tcx> {
         span: Span,
         fn_abi_request: FnAbiRequest<'tcx>,
     ) -> ! {
-        match err {
-            FnAbiError::Layout(LayoutError::SizeOverflow(_) | LayoutError::InvalidSimd { .. }) => {
-                self.tcx.dcx().emit_fatal(Spanned { span, node: err });
-            }
-            _ => match fn_abi_request {
-                FnAbiRequest::OfFnPtr { sig, extra_args } => {
-                    span_bug!(span, "`fn_abi_of_fn_ptr({sig}, {extra_args:?})` failed: {err:?}",);
-                }
-                FnAbiRequest::OfInstance { instance, extra_args } => {
-                    span_bug!(
-                        span,
-                        "`fn_abi_of_instance({instance}, {extra_args:?})` failed: {err:?}",
-                    );
-                }
-            },
-        }
+        codegen_handle_fn_abi_err(self.tcx, err, span, fn_abi_request).raise_fatal()
     }
 }

compiler/rustc_codegen_llvm/src/intrinsic.rs

@@ -231,11 +231,11 @@ impl<'ll, 'tcx> IntrinsicCallBuilderMethods<'tcx> for Builder<'_, 'll, 'tcx> {
             }
             sym::offload => {
                 if tcx.sess.opts.unstable_opts.offload.is_empty() {
-                    let _ = tcx.dcx().emit_almost_fatal(OffloadWithoutEnable);
+                    let _ = tcx.dcx().emit_err(OffloadWithoutEnable);
                 }
 
                 if tcx.sess.lto() != rustc_session::config::Lto::Fat {
-                    let _ = tcx.dcx().emit_almost_fatal(OffloadWithoutFatLTO);
+                    let _ = tcx.dcx().emit_err(OffloadWithoutFatLTO);
                 }
 
                 codegen_offload(self, tcx, instance, args);
@@ -1752,18 +1752,18 @@ fn codegen_autodiff<'ll, 'tcx>(
 ) -> IntrinsicResult<'tcx, &'ll Value> {
     let tcx = bx.tcx;
     if !tcx.sess.opts.unstable_opts.autodiff.contains(&rustc_session::config::AutoDiff::Enable) {
-        let _ = tcx.dcx().emit_almost_fatal(AutoDiffWithoutEnable);
+        let _ = tcx.dcx().emit_err(AutoDiffWithoutEnable);
     }
 
     let ct = tcx.crate_types();
     let lto = tcx.sess.lto();
     if ct.len() == 1 && ct.contains(&CrateType::Executable) {
         if lto != rustc_session::config::Lto::Fat {
-            let _ = tcx.dcx().emit_almost_fatal(AutoDiffWithoutLto);
+            let _ = tcx.dcx().emit_err(AutoDiffWithoutLto);
         }
     } else {
         if lto != rustc_session::config::Lto::Fat && !tcx.sess.opts.cg.linker_plugin_lto.enabled() {
-            let _ = tcx.dcx().emit_almost_fatal(AutoDiffWithoutLto);
+            let _ = tcx.dcx().emit_err(AutoDiffWithoutLto);
         }
     }
 

compiler/rustc_errors/src/diagnostic.rs

@@ -73,13 +73,6 @@ impl EmissionGuarantee for FatalAbort {
     }
 }
 
-impl EmissionGuarantee for rustc_span::fatal_error::FatalError {
-    fn emit_producing_guarantee(diag: Diag<'_, Self>) -> Self::EmitResult {
-        diag.emit_producing_nothing();
-        rustc_span::fatal_error::FatalError
-    }
-}
-
 /// Trait implemented by error types. This is rarely implemented manually. Instead, use
 /// `#[derive(Diagnostic)]` -- see [rustc_macros::Diagnostic].
 ///

compiler/rustc_errors/src/lib.rs

@@ -1025,19 +1025,6 @@ impl<'a> DiagCtxtHandle<'a> {
         self.create_fatal(fatal).emit()
     }
 
-    #[track_caller]
-    pub fn create_almost_fatal(
-        self,
-        fatal: impl Diagnostic<'a, FatalError>,
-    ) -> Diag<'a, FatalError> {
-        fatal.into_diag(self, Fatal)
-    }
-
-    #[track_caller]
-    pub fn emit_almost_fatal(self, fatal: impl Diagnostic<'a, FatalError>) -> FatalError {
-        self.create_almost_fatal(fatal).emit()
-    }
-
     // FIXME: This method should be removed (every error should have an associated error code).
     #[track_caller]
     pub fn struct_err(self, msg: impl Into<DiagMessage>) -> Diag<'a> {
@@ -1577,24 +1564,21 @@ impl DelayedDiagInner {
     }
 }
 
-/// | Level        | is_error | EmissionGuarantee            | Top-level | Sub | Used in lints?
-/// | -----        | -------- | -----------------            | --------- | --- | --------------
-/// | Bug          | yes      | BugAbort                     | yes       | -   | -
-/// | Fatal        | yes      | FatalAbort/FatalError[^star] | yes       | -   | -
-/// | Error        | yes      | ErrorGuaranteed              | yes       | -   | yes
-/// | DelayedBug   | yes      | ErrorGuaranteed              | yes       | -   | -
-/// | ForceWarning | -        | ()                           | yes       | -   | lint-only
-/// | Warning      | -        | ()                           | yes       | yes | yes
-/// | Note         | -        | ()                           | rare      | yes | -
-/// | OnceNote     | -        | ()                           | -         | yes | lint-only
-/// | Help         | -        | ()                           | rare      | yes | -
-/// | OnceHelp     | -        | ()                           | -         | yes | lint-only
-/// | FailureNote  | -        | ()                           | rare      | -   | -
-/// | Allow        | -        | ()                           | yes       | -   | lint-only
-/// | Expect       | -        | ()                           | yes       | -   | lint-only
-///
-/// [^star]: `FatalAbort` normally, `FatalError` in the non-aborting "almost fatal" case that is
-///     occasionally used.
+/// | Level        | is_error | EmissionGuarantee | Top-level | Sub | Used in lints?
+/// | -----        | -------- | ----------------- | --------- | --- | --------------
+/// | Bug          | yes      | BugAbort          | yes       | -   | -
+/// | Fatal        | yes      | FatalAbort        | yes       | -   | -
+/// | Error        | yes      | ErrorGuaranteed   | yes       | -   | yes
+/// | DelayedBug   | yes      | ErrorGuaranteed   | yes       | -   | -
+/// | ForceWarning | -        | ()                | yes       | -   | lint-only
+/// | Warning      | -        | ()                | yes       | yes | yes
+/// | Note         | -        | ()                | rare      | yes | -
+/// | OnceNote     | -        | ()                | -         | yes | lint-only
+/// | Help         | -        | ()                | rare      | yes | -
+/// | OnceHelp     | -        | ()                | -         | yes | lint-only
+/// | FailureNote  | -        | ()                | rare      | -   | -
+/// | Allow        | -        | ()                | yes       | -   | lint-only
+/// | Expect       | -        | ()                | yes       | -   | lint-only
 ///
 #[derive(Copy, PartialEq, Eq, Clone, Hash, Debug, Encodable, Decodable)]
 pub enum Level {

compiler/rustc_interface/src/passes.rs

@@ -1302,7 +1302,10 @@ pub(crate) fn start_codegen<'tcx>(
 
     info!("Pre-codegen\n{:?}", tcx.debug_stats());
 
-    let metadata = rustc_metadata::fs::encode_and_write_metadata(tcx);
+    let metadata = match rustc_metadata::fs::encode_and_write_metadata(tcx) {
+        Ok(metadata) => metadata,
+        Err(guar) => guar.raise_fatal(),
+    };
 
     let is_host_metadata = tcx
         .sess

compiler/rustc_metadata/src/fs.rs

@@ -7,6 +7,7 @@ use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
 use rustc_session::config::{OutFileName, OutputType};
 use rustc_session::output::filename_for_metadata;
+use rustc_span::ErrorGuaranteed;
 use rustc_structures::CrateType;
 
 use crate::diagnostics::{
@@ -34,7 +35,7 @@ pub fn emit_wrapper_file(sess: &Session, data: &[u8], tmpdir: &Path, name: &str)
     out_filename
 }
 
-pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
+pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> Result<EncodedMetadata, ErrorGuaranteed> {
     let out_filename = filename_for_metadata(tcx.sess, tcx.output_filenames(()));
     // To avoid races with another rustc process scanning the output directory,
     // we need to write the file somewhere else and atomically move it to its
@@ -70,6 +71,10 @@ pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
         }
     }
 
+    if let Some(guar) = tcx.sess.dcx().has_errors_or_delayed_bugs() {
+        return Err(guar);
+    }
+
     let _prof_timer = tcx.sess.prof.generic_activity("write_crate_metadata");
 
     // If the user requests metadata as output, rename `metadata_filename`
@@ -109,7 +114,7 @@ pub fn encode_and_write_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
                 tcx.dcx().emit_fatal(FailedCreateEncodedMetadata { err });
             });
 
-    metadata
+    Ok(metadata)
 }
 
 #[cfg(not(target_os = "linux"))]

compiler/rustc_metadata/src/native_libs.rs

@@ -274,7 +274,8 @@ impl<'tcx> Collector<'tcx> {
                     DllCallingConvention::Vectorcall(self.i686_arg_list_size(item))
                 }
                 _ => {
-                    self.tcx.dcx().emit_fatal(diagnostics::RawDylibUnsupportedAbi { span });
+                    self.tcx.dcx().emit_err(diagnostics::RawDylibUnsupportedAbi { span });
+                    return None;
                 }
             }
         } else {
@@ -283,7 +284,8 @@ impl<'tcx> Collector<'tcx> {
                     DllCallingConvention::C
                 }
                 _ => {
-                    self.tcx.dcx().emit_fatal(diagnostics::RawDylibUnsupportedAbi { span });
+                    self.tcx.dcx().emit_err(diagnostics::RawDylibUnsupportedAbi { span });
+                    return None;
                 }
             }
         };

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1571,8 +1571,19 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
             }
             if let DefKind::Static { .. } = def_kind {
                 if !self.tcx.is_foreign_item(def_id) {
-                    let data = self.tcx.eval_static_initializer(def_id).unwrap();
-                    record!(self.tables.eval_static_initializer[def_id] <- data);
+                    match self.tcx.eval_static_initializer(def_id) {
+                        Ok(data) => record!(self.tables.eval_static_initializer[def_id] <- data),
+                        Err(err) => match err {
+                            interpret::ErrorHandled::Reported(_, _) => {
+                                self.tcx.dcx().delayed_bug(format!(
+                                    "eval_static_initializer returned an error in metadata emission"
+                                ));
+                            }
+                            interpret::ErrorHandled::TooGeneric(span) => {
+                                span_bug!(span, "generic static???");
+                            }
+                        },
+                    };
                 }
             }
             if let DefKind::Enum | DefKind::Struct | DefKind::Union = def_kind {

compiler/rustc_middle/src/ty/layout.rs

@@ -14,7 +14,7 @@ use rustc_hir::attrs::lang_items::LangItem;
 use rustc_hir::def_id::DefId;
 use rustc_macros::{StableHash, TyDecodable, TyEncodable, extension};
 use rustc_session::config::OptLevel;
-use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, Symbol, sym};
+use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, Spanned, Symbol, sym};
 use rustc_structures::Limit;
 use rustc_target::callconv::FnAbi;
 use rustc_target::spec::{HasTargetSpec, HasX86AbiOpt, Target, X86Abi};
@@ -1374,6 +1374,8 @@ pub trait FnAbiOfHelpers<'tcx>: LayoutOfHelpers<'tcx> {
     /// but this hook allows e.g. codegen to return only `&FnAbi` from its
     /// `cx.fn_abi_of_*(...)`, without any `Result<...>` around it to deal with
     /// (and any `FnAbiError`s are turned into fatal errors or ICEs).
+    ///
+    /// Codegen backends should use [`codegen_handle_fn_abi_err`] as implementation.
     fn handle_fn_abi_err(
         &self,
         err: FnAbiError<'tcx>,
@@ -1382,6 +1384,28 @@ pub trait FnAbiOfHelpers<'tcx>: LayoutOfHelpers<'tcx> {
     ) -> <Self::FnAbiOfResult as MaybeResult<&'tcx FnAbi<'tcx, Ty<'tcx>>>>::Error;
 }
 
+/// Implementation of [`FnAbiOfHelpers::handle_fn_abi_err`] for codegen backends.
+pub fn codegen_handle_fn_abi_err<'tcx>(
+    tcx: TyCtxt<'tcx>,
+    err: FnAbiError<'tcx>,
+    span: Span,
+    fn_abi_request: FnAbiRequest<'tcx>,
+) -> ErrorGuaranteed {
+    match err {
+        FnAbiError::Layout(LayoutError::SizeOverflow(_) | LayoutError::InvalidSimd { .. }) => {
+            tcx.dcx().emit_err(Spanned { span, node: err })
+        }
+        _ => match fn_abi_request {
+            FnAbiRequest::OfFnPtr { sig, extra_args } => {
+                span_bug!(span, "`fn_abi_of_fn_ptr({sig}, {extra_args:?})` failed: {err:?}",);
+            }
+            FnAbiRequest::OfInstance { instance, extra_args } => {
+                span_bug!(span, "`fn_abi_of_instance({instance}, {extra_args:?})` failed: {err:?}",);
+            }
+        },
+    }
+}
+
 /// Blanket extension trait for contexts that can compute `FnAbi`s.
 pub trait FnAbiOf<'tcx>: FnAbiOfHelpers<'tcx> {
     /// Compute a `FnAbi` suitable for indirect calls, i.e. to `fn` pointers.