Rollup merge of #154449 - nnethercote:rustc_errors-dep-rustc_abi, r=davidtwco

Invert dependency between `rustc_errors` and `rustc_abi`.

Currently, `rustc_errors` depends on `rustc_abi`, which depends on `rustc_error_messages`. This is a bit odd.

`rustc_errors` depends on `rustc_abi` for a single reason: `rustc_abi` defines a type `TargetDataLayoutErrors` and `rustc_errors` impls `Diagnostic` for that type.

We can get a more natural relationship by inverting the dependency, moving the `Diagnostic` trait upstream. Then `rustc_abi` defines `TargetDataLayoutErrors` and also impls `Diagnostic` for it. `rustc_errors` is already pretty far upstream in the crate graph, it doesn't hurt to push it a little further because errors are a very low-level concept.

r? @davidtwco

Author: JonathanBrouwer

Cargo.lock

@@ -3505,6 +3505,7 @@ dependencies = [
  "rand_xoshiro",
  "rustc_data_structures",
  "rustc_error_messages",
+ "rustc_errors",
  "rustc_hashes",
  "rustc_index",
  "rustc_macros",
@@ -3909,7 +3910,6 @@ dependencies = [
  "anstream",
  "anstyle",
  "derive_setters",
- "rustc_abi",
  "rustc_ast",
  "rustc_data_structures",
  "rustc_error_codes",

compiler/rustc_abi/Cargo.toml

@@ -10,6 +10,7 @@ rand = { version = "0.9.0", default-features = false, optional = true }
 rand_xoshiro = { version = "0.7.0", optional = true }
 rustc_data_structures = { path = "../rustc_data_structures", optional = true }
 rustc_error_messages = { path = "../rustc_error_messages", optional = true }
+rustc_errors = { path = "../rustc_errors", optional = true }
 rustc_hashes = { path = "../rustc_hashes" }
 rustc_index = { path = "../rustc_index", default-features = false }
 rustc_macros = { path = "../rustc_macros", optional = true }
@@ -21,11 +22,12 @@ tracing = "0.1"
 [features]
 # tidy-alphabetical-start
 default = ["nightly", "randomize"]
-# rust-analyzer depends on this crate and we therefore require it to built on a stable toolchain
-# without depending on rustc_data_structures, rustc_macros and rustc_serialize
+# rust-analyzer depends on this crate and we therefore require it to build on a stable toolchain
+# without depending on the rustc_* crates in the following list.
 nightly = [
     "dep:rustc_data_structures",
     "dep:rustc_error_messages",
+    "dep:rustc_errors",
     "dep:rustc_macros",
     "dep:rustc_serialize",
     "dep:rustc_span",

compiler/rustc_abi/src/lib.rs

@@ -46,6 +46,8 @@ use std::str::FromStr;
 use bitflags::bitflags;
 #[cfg(feature = "nightly")]
 use rustc_data_structures::stable_hasher::StableOrd;
+#[cfg(feature = "nightly")]
+use rustc_errors::{Diag, DiagCtxtHandle, Diagnostic, EmissionGuarantee, Level, msg};
 use rustc_hashes::Hash64;
 use rustc_index::{Idx, IndexSlice, IndexVec};
 #[cfg(feature = "nightly")]
@@ -332,7 +334,7 @@ impl Default for TargetDataLayout {
     }
 }
 
-pub enum TargetDataLayoutErrors<'a> {
+pub enum TargetDataLayoutError<'a> {
     InvalidAddressSpace { addr_space: &'a str, cause: &'a str, err: ParseIntError },
     InvalidBits { kind: &'a str, bit: &'a str, cause: &'a str, err: ParseIntError },
     MissingAlignment { cause: &'a str },
@@ -343,6 +345,51 @@ pub enum TargetDataLayoutErrors<'a> {
     UnknownPointerSpecification { err: String },
 }
 
+#[cfg(feature = "nightly")]
+impl<G: EmissionGuarantee> Diagnostic<'_, G> for TargetDataLayoutError<'_> {
+    fn into_diag(self, dcx: DiagCtxtHandle<'_>, level: Level) -> Diag<'_, G> {
+        match self {
+            TargetDataLayoutError::InvalidAddressSpace { addr_space, err, cause } => {
+                Diag::new(dcx, level, msg!("invalid address space `{$addr_space}` for `{$cause}` in \"data-layout\": {$err}"))
+                    .with_arg("addr_space", addr_space)
+                    .with_arg("cause", cause)
+                    .with_arg("err", err)
+            }
+            TargetDataLayoutError::InvalidBits { kind, bit, cause, err } => {
+                Diag::new(dcx, level, msg!("invalid {$kind} `{$bit}` for `{$cause}` in \"data-layout\": {$err}"))
+                    .with_arg("kind", kind)
+                    .with_arg("bit", bit)
+                    .with_arg("cause", cause)
+                    .with_arg("err", err)
+            }
+            TargetDataLayoutError::MissingAlignment { cause } => {
+                Diag::new(dcx, level, msg!("missing alignment for `{$cause}` in \"data-layout\""))
+                    .with_arg("cause", cause)
+            }
+            TargetDataLayoutError::InvalidAlignment { cause, err } => {
+                Diag::new(dcx, level, msg!("invalid alignment for `{$cause}` in \"data-layout\": {$err}"))
+                    .with_arg("cause", cause)
+                    .with_arg("err", err.to_string())
+            }
+            TargetDataLayoutError::InconsistentTargetArchitecture { dl, target } => {
+                Diag::new(dcx, level, msg!("inconsistent target specification: \"data-layout\" claims architecture is {$dl}-endian, while \"target-endian\" is `{$target}`"))
+                    .with_arg("dl", dl).with_arg("target", target)
+            }
+            TargetDataLayoutError::InconsistentTargetPointerWidth { pointer_size, target } => {
+                Diag::new(dcx, level, msg!("inconsistent target specification: \"data-layout\" claims pointers are {$pointer_size}-bit, while \"target-pointer-width\" is `{$target}`"))
+                    .with_arg("pointer_size", pointer_size).with_arg("target", target)
+            }
+            TargetDataLayoutError::InvalidBitsSize { err } => {
+                Diag::new(dcx, level, msg!("{$err}")).with_arg("err", err)
+            }
+            TargetDataLayoutError::UnknownPointerSpecification { err } => {
+                Diag::new(dcx, level, msg!("unknown pointer specification `{$err}` in datalayout string"))
+                    .with_arg("err", err)
+            }
+        }
+    }
+}
+
 impl TargetDataLayout {
     /// Parse data layout from an
     /// [llvm data layout string](https://llvm.org/docs/LangRef.html#data-layout)
@@ -352,17 +399,17 @@ impl TargetDataLayout {
     pub fn parse_from_llvm_datalayout_string<'a>(
         input: &'a str,
         default_address_space: AddressSpace,
-    ) -> Result<TargetDataLayout, TargetDataLayoutErrors<'a>> {
+    ) -> Result<TargetDataLayout, TargetDataLayoutError<'a>> {
         // Parse an address space index from a string.
         let parse_address_space = |s: &'a str, cause: &'a str| {
             s.parse::<u32>().map(AddressSpace).map_err(|err| {
-                TargetDataLayoutErrors::InvalidAddressSpace { addr_space: s, cause, err }
+                TargetDataLayoutError::InvalidAddressSpace { addr_space: s, cause, err }
             })
         };
 
         // Parse a bit count from a string.
         let parse_bits = |s: &'a str, kind: &'a str, cause: &'a str| {
-            s.parse::<u64>().map_err(|err| TargetDataLayoutErrors::InvalidBits {
+            s.parse::<u64>().map_err(|err| TargetDataLayoutError::InvalidBits {
                 kind,
                 bit: s,
                 cause,
@@ -378,7 +425,7 @@ impl TargetDataLayout {
         let parse_align_str = |s: &'a str, cause: &'a str| {
             let align_from_bits = |bits| {
                 Align::from_bits(bits)
-                    .map_err(|err| TargetDataLayoutErrors::InvalidAlignment { cause, err })
+                    .map_err(|err| TargetDataLayoutError::InvalidAlignment { cause, err })
             };
             let abi = parse_bits(s, "alignment", cause)?;
             Ok(align_from_bits(abi)?)
@@ -388,7 +435,7 @@ impl TargetDataLayout {
         // ignoring the secondary alignment specifications.
         let parse_align_seq = |s: &[&'a str], cause: &'a str| {
             if s.is_empty() {
-                return Err(TargetDataLayoutErrors::MissingAlignment { cause });
+                return Err(TargetDataLayoutError::MissingAlignment { cause });
             }
             parse_align_str(s[0], cause)
         };
@@ -426,7 +473,7 @@ impl TargetDataLayout {
                     // However, we currently don't take into account further specifications:
                     // an error is emitted instead.
                     if p.starts_with(char::is_alphabetic) {
-                        return Err(TargetDataLayoutErrors::UnknownPointerSpecification {
+                        return Err(TargetDataLayoutError::UnknownPointerSpecification {
                             err: p.to_string(),
                         });
                     }
@@ -471,7 +518,7 @@ impl TargetDataLayout {
                     // However, we currently don't take into account further specifications:
                     // an error is emitted instead.
                     if p.starts_with(char::is_alphabetic) {
-                        return Err(TargetDataLayoutErrors::UnknownPointerSpecification {
+                        return Err(TargetDataLayoutError::UnknownPointerSpecification {
                             err: p.to_string(),
                         });
                     }

compiler/rustc_codegen_ssa/src/lib.rs

@@ -256,7 +256,7 @@ pub struct CompiledModules {
     pub allocator_module: Option<CompiledModule>,
 }
 
-pub enum CodegenErrors {
+pub enum CodegenError {
     WrongFileType,
     EmptyVersionNumber,
     EncodingVersionMismatch { version_array: String, rlink_version: u32 },
@@ -317,32 +317,32 @@ impl CompiledModules {
     pub fn deserialize_rlink(
         sess: &Session,
         data: Vec<u8>,
-    ) -> Result<(Self, CrateInfo, EncodedMetadata, OutputFilenames), CodegenErrors> {
+    ) -> Result<(Self, CrateInfo, EncodedMetadata, OutputFilenames), CodegenError> {
         // The Decodable machinery is not used here because it panics if the input data is invalid
         // and because its internal representation may change.
         if !data.starts_with(RLINK_MAGIC) {
-            return Err(CodegenErrors::WrongFileType);
+            return Err(CodegenError::WrongFileType);
         }
         let data = &data[RLINK_MAGIC.len()..];
         if data.len() < 4 {
-            return Err(CodegenErrors::EmptyVersionNumber);
+            return Err(CodegenError::EmptyVersionNumber);
         }
 
         let mut version_array: [u8; 4] = Default::default();
         version_array.copy_from_slice(&data[..4]);
         if u32::from_be_bytes(version_array) != RLINK_VERSION {
-            return Err(CodegenErrors::EncodingVersionMismatch {
+            return Err(CodegenError::EncodingVersionMismatch {
                 version_array: String::from_utf8_lossy(&version_array).to_string(),
                 rlink_version: RLINK_VERSION,
             });
         }
 
         let Ok(mut decoder) = MemDecoder::new(&data[4..], 0) else {
-            return Err(CodegenErrors::CorruptFile);
+            return Err(CodegenError::CorruptFile);
         };
         let rustc_version = decoder.read_str();
         if rustc_version != sess.cfg_version {
-            return Err(CodegenErrors::RustcVersionMismatch {
+            return Err(CodegenError::RustcVersionMismatch {
                 rustc_version: rustc_version.to_string(),
             });
         }

compiler/rustc_driver_impl/src/lib.rs

@@ -28,7 +28,7 @@ use std::{env, str};
 
 use rustc_ast as ast;
 use rustc_codegen_ssa::traits::CodegenBackend;
-use rustc_codegen_ssa::{CodegenErrors, CompiledModules};
+use rustc_codegen_ssa::{CodegenError, CompiledModules};
 use rustc_data_structures::profiling::{
     TimePassesFormat, get_resident_set_size, print_time_passes_entry,
 };
@@ -567,23 +567,21 @@ fn process_rlink(sess: &Session, compiler: &interface::Compiler) {
                 }
                 Err(err) => {
                     match err {
-                        CodegenErrors::WrongFileType => dcx.emit_fatal(RLinkWrongFileType),
-                        CodegenErrors::EmptyVersionNumber => {
-                            dcx.emit_fatal(RLinkEmptyVersionNumber)
-                        }
-                        CodegenErrors::EncodingVersionMismatch { version_array, rlink_version } => {
+                        CodegenError::WrongFileType => dcx.emit_fatal(RLinkWrongFileType),
+                        CodegenError::EmptyVersionNumber => dcx.emit_fatal(RLinkEmptyVersionNumber),
+                        CodegenError::EncodingVersionMismatch { version_array, rlink_version } => {
                             dcx.emit_fatal(RLinkEncodingVersionMismatch {
                                 version_array,
                                 rlink_version,
                             })
                         }
-                        CodegenErrors::RustcVersionMismatch { rustc_version } => {
+                        CodegenError::RustcVersionMismatch { rustc_version } => {
                             dcx.emit_fatal(RLinkRustcVersionMismatch {
                                 rustc_version,
                                 current_version: sess.cfg_version,
                             })
                         }
-                        CodegenErrors::CorruptFile => {
+                        CodegenError::CorruptFile => {
                             dcx.emit_fatal(RlinkCorruptFile { file });
                         }
                     };

compiler/rustc_errors/Cargo.toml

@@ -9,7 +9,6 @@ annotate-snippets = { version = "0.12.15", features = ["simd"] }
 anstream = "0.6.20"
 anstyle = "1.0.13"
 derive_setters = "0.1.6"
-rustc_abi = { path = "../rustc_abi" }
 rustc_ast = { path = "../rustc_ast" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_error_codes = { path = "../rustc_error_codes" }

compiler/rustc_errors/src/diagnostic_impls.rs

@@ -1,12 +1,11 @@
 use std::borrow::Cow;
 
-use rustc_abi::TargetDataLayoutErrors;
 use rustc_error_messages::{DiagArgValue, IntoDiagArg};
 use rustc_macros::Subdiagnostic;
 use rustc_span::{Span, Symbol};
 
 use crate::diagnostic::DiagLocation;
-use crate::{Diag, DiagCtxtHandle, Diagnostic, EmissionGuarantee, Level, Subdiagnostic, msg};
+use crate::{Diag, EmissionGuarantee, Subdiagnostic};
 
 impl IntoDiagArg for DiagLocation {
     fn into_diag_arg(self, _: &mut Option<std::path::PathBuf>) -> DiagArgValue {
@@ -37,55 +36,6 @@ impl<S: std::fmt::Display> IntoDiagArg for DiagSymbolList<S> {
     }
 }
 
-impl<G: EmissionGuarantee> Diagnostic<'_, G> for TargetDataLayoutErrors<'_> {
-    fn into_diag(self, dcx: DiagCtxtHandle<'_>, level: Level) -> Diag<'_, G> {
-        match self {
-            TargetDataLayoutErrors::InvalidAddressSpace { addr_space, err, cause } => {
-                Diag::new(dcx, level, msg!("invalid address space `{$addr_space}` for `{$cause}` in \"data-layout\": {$err}"))
-                    .with_arg("addr_space", addr_space)
-                    .with_arg("cause", cause)
-                    .with_arg("err", err)
-            }
-            TargetDataLayoutErrors::InvalidBits { kind, bit, cause, err } => {
-                Diag::new(dcx, level, msg!("invalid {$kind} `{$bit}` for `{$cause}` in \"data-layout\": {$err}"))
-                    .with_arg("kind", kind)
-                    .with_arg("bit", bit)
-                    .with_arg("cause", cause)
-                    .with_arg("err", err)
-            }
-            TargetDataLayoutErrors::MissingAlignment { cause } => {
-                Diag::new(dcx, level, msg!("missing alignment for `{$cause}` in \"data-layout\""))
-                    .with_arg("cause", cause)
-            }
-            TargetDataLayoutErrors::InvalidAlignment { cause, err } => {
-                Diag::new(dcx, level, msg!(
-                    "invalid alignment for `{$cause}` in \"data-layout\": {$err}"
-                ))
-                .with_arg("cause", cause)
-                .with_arg("err", err.to_string())
-            }
-            TargetDataLayoutErrors::InconsistentTargetArchitecture { dl, target } => {
-                Diag::new(dcx, level, msg!(
-                    "inconsistent target specification: \"data-layout\" claims architecture is {$dl}-endian, while \"target-endian\" is `{$target}`"
-                ))
-                .with_arg("dl", dl).with_arg("target", target)
-            }
-            TargetDataLayoutErrors::InconsistentTargetPointerWidth { pointer_size, target } => {
-                Diag::new(dcx, level, msg!(
-                    "inconsistent target specification: \"data-layout\" claims pointers are {$pointer_size}-bit, while \"target-pointer-width\" is `{$target}`"
-                )).with_arg("pointer_size", pointer_size).with_arg("target", target)
-            }
-            TargetDataLayoutErrors::InvalidBitsSize { err } => {
-                Diag::new(dcx, level, msg!("{$err}")).with_arg("err", err)
-            }
-            TargetDataLayoutErrors::UnknownPointerSpecification { err } => {
-                Diag::new(dcx, level, msg!("unknown pointer specification `{$err}` in datalayout string"))
-                    .with_arg("err", err)
-            }
-        }
-    }
-}
-
 /// Utility struct used to apply a single label while highlighting multiple spans
 pub struct SingleLabelManySpans {
     pub spans: Vec<Span>,

compiler/rustc_target/src/spec/mod.rs

@@ -47,7 +47,7 @@ use std::str::FromStr;
 use std::{fmt, io};
 
 use rustc_abi::{
-    Align, CanonAbi, Endian, ExternAbi, Integer, Size, TargetDataLayout, TargetDataLayoutErrors,
+    Align, CanonAbi, Endian, ExternAbi, Integer, Size, TargetDataLayout, TargetDataLayoutError,
 };
 use rustc_data_structures::fx::{FxHashSet, FxIndexSet};
 use rustc_error_messages::{DiagArgValue, IntoDiagArg, into_diag_arg_using_display};
@@ -2166,15 +2166,15 @@ pub struct TargetMetadata {
 }
 
 impl Target {
-    pub fn parse_data_layout(&self) -> Result<TargetDataLayout, TargetDataLayoutErrors<'_>> {
+    pub fn parse_data_layout(&self) -> Result<TargetDataLayout, TargetDataLayoutError<'_>> {
         let mut dl = TargetDataLayout::parse_from_llvm_datalayout_string(
             &self.data_layout,
             self.options.default_address_space,
         )?;
 
         // Perform consistency checks against the Target information.
         if dl.endian != self.endian {
-            return Err(TargetDataLayoutErrors::InconsistentTargetArchitecture {
+            return Err(TargetDataLayoutError::InconsistentTargetArchitecture {
                 dl: dl.endian.as_str(),
                 target: self.endian.as_str(),
             });
@@ -2183,7 +2183,7 @@ impl Target {
         let target_pointer_width: u64 = self.pointer_width.into();
         let dl_pointer_size: u64 = dl.pointer_size().bits();
         if dl_pointer_size != target_pointer_width {
-            return Err(TargetDataLayoutErrors::InconsistentTargetPointerWidth {
+            return Err(TargetDataLayoutError::InconsistentTargetPointerWidth {
                 pointer_size: dl_pointer_size,
                 target: self.pointer_width,
             });
@@ -2192,7 +2192,7 @@ impl Target {
         dl.c_enum_min_size = Integer::from_size(Size::from_bits(
             self.c_enum_min_bits.unwrap_or(self.c_int_width as _),
         ))
-        .map_err(|err| TargetDataLayoutErrors::InvalidBitsSize { err })?;
+        .map_err(|err| TargetDataLayoutError::InvalidBitsSize { err })?;
 
         Ok(dl)
     }