Migrate rustc_driver to SessionDiagnostic

Cargo.lock

@@ -3820,6 +3820,7 @@ dependencies = [
  "rustc_interface",
  "rustc_lint",
  "rustc_log",
+ "rustc_macros",
  "rustc_metadata",
  "rustc_middle",
  "rustc_parse",

compiler/rustc_codegen_ssa/src/lib.rs

@@ -168,6 +168,13 @@ pub struct CodegenResults {
     pub crate_info: CrateInfo,
 }
 
+pub enum CodegenErrors<'a> {
+    WrongFileType,
+    EmptyVersionNumber,
+    EncodingVersionMismatch { version_array: String, rlink_version: u32 },
+    RustcVersionMismatch { rustc_version: String, current_version: &'a str },
+}
+
 pub fn provide(providers: &mut Providers) {
     crate::back::symbol_export::provide(providers);
     crate::base::provide(providers);
@@ -212,30 +219,34 @@ impl CodegenResults {
         encoder.finish()
     }
 
-    pub fn deserialize_rlink(data: Vec<u8>) -> Result<Self, String> {
+    pub fn deserialize_rlink<'a>(data: Vec<u8>) -> Result<Self, CodegenErrors<'a>> {
         // 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("The input does not look like a .rlink file".to_string());
+            return Err(CodegenErrors::WrongFileType);
         }
         let data = &data[RLINK_MAGIC.len()..];
         if data.len() < 4 {
-            return Err("The input does not contain version number".to_string());
+            return Err(CodegenErrors::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(".rlink file was produced with encoding version {version_array}, but the current version is {RLINK_VERSION}".to_string());
+            return Err(CodegenErrors::EncodingVersionMismatch {
+                version_array: String::from_utf8_lossy(&version_array).to_string(),
+                rlink_version: RLINK_VERSION,
+            });
         }
 
         let mut decoder = MemDecoder::new(&data[4..], 0);
         let rustc_version = decoder.read_str();
         let current_version = RUSTC_VERSION.unwrap();
         if rustc_version != current_version {
-            return Err(format!(
-                ".rlink file was produced by rustc version {rustc_version}, but the current version is {current_version}."
-            ));
+            return Err(CodegenErrors::RustcVersionMismatch {
+                rustc_version: rustc_version.to_string(),
+                current_version,
+            });
         }
 
         let codegen_results = CodegenResults::decode(&mut decoder);

compiler/rustc_driver/Cargo.toml

@@ -19,6 +19,7 @@ rustc_errors = { path = "../rustc_errors" }
 rustc_feature = { path = "../rustc_feature" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_hir_pretty = { path = "../rustc_hir_pretty" }
+rustc_macros = { path = "../rustc_macros" }
 rustc_metadata = { path = "../rustc_metadata" }
 rustc_parse = { path = "../rustc_parse" }
 rustc_plugin_impl = { path = "../rustc_plugin_impl" }

compiler/rustc_driver/src/lib.rs

@@ -9,14 +9,16 @@
 #![feature(once_cell)]
 #![recursion_limit = "256"]
 #![allow(rustc::potential_query_instability)]
+#![deny(rustc::untranslatable_diagnostic)]
+#![deny(rustc::diagnostic_outside_of_impl)]
 
 #[macro_use]
 extern crate tracing;
 
 pub extern crate rustc_plugin_impl as plugin;
 
 use rustc_ast as ast;
-use rustc_codegen_ssa::{traits::CodegenBackend, CodegenResults};
+use rustc_codegen_ssa::{traits::CodegenBackend, CodegenErrors, CodegenResults};
 use rustc_data_structures::profiling::{get_resident_set_size, print_time_passes_entry};
 use rustc_data_structures::sync::SeqCst;
 use rustc_errors::registry::{InvalidErrorCode, Registry};
@@ -56,6 +58,12 @@ use std::time::Instant;
 
 pub mod args;
 pub mod pretty;
+mod session_diagnostics;
+
+use crate::session_diagnostics::{
+    RLinkEmptyVersionNumber, RLinkEncodingVersionMismatch, RLinkRustcVersionMismatch,
+    RLinkWrongFileType, RlinkNotAFile, RlinkUnableToRead,
+};
 
 /// Exit status code used for successful compilation and help output.
 pub const EXIT_SUCCESS: i32 = 0;
@@ -581,18 +589,35 @@ pub fn try_process_rlink(sess: &Session, compiler: &interface::Compiler) -> Comp
             sess.init_crate_types(collect_crate_types(sess, &[]));
             let outputs = compiler.build_output_filenames(sess, &[]);
             let rlink_data = fs::read(file).unwrap_or_else(|err| {
-                sess.fatal(&format!("failed to read rlink file: {}", err));
+                sess.emit_fatal(RlinkUnableToRead { err });
             });
             let codegen_results = match CodegenResults::deserialize_rlink(rlink_data) {
                 Ok(codegen) => codegen,
-                Err(error) => {
-                    sess.fatal(&format!("Could not deserialize .rlink file: {error}"));
+                Err(err) => {
+                    match err {
+                        CodegenErrors::WrongFileType => sess.emit_fatal(RLinkWrongFileType),
+                        CodegenErrors::EmptyVersionNumber => {
+                            sess.emit_fatal(RLinkEmptyVersionNumber)
+                        }
+                        CodegenErrors::EncodingVersionMismatch { version_array, rlink_version } => {
+                            sess.emit_fatal(RLinkEncodingVersionMismatch {
+                                version_array,
+                                rlink_version,
+                            })
+                        }
+                        CodegenErrors::RustcVersionMismatch { rustc_version, current_version } => {
+                            sess.emit_fatal(RLinkRustcVersionMismatch {
+                                rustc_version,
+                                current_version,
+                            })
+                        }
+                    };
                 }
             };
             let result = compiler.codegen_backend().link(sess, codegen_results, &outputs);
             abort_on_err(result, sess);
         } else {
-            sess.fatal("rlink must be a file")
+            sess.emit_fatal(RlinkNotAFile {})
         }
         Compilation::Stop
     } else {

compiler/rustc_driver/src/session_diagnostics.rs

@@ -0,0 +1,33 @@
+use rustc_macros::SessionDiagnostic;
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_unable_to_read)]
+pub(crate) struct RlinkUnableToRead {
+    pub err: std::io::Error,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_wrong_file_type)]
+pub(crate) struct RLinkWrongFileType;
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_empty_version_number)]
+pub(crate) struct RLinkEmptyVersionNumber;
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_encoding_version_mismatch)]
+pub(crate) struct RLinkEncodingVersionMismatch {
+    pub version_array: String,
+    pub rlink_version: u32,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_rustc_version_mismatch)]
+pub(crate) struct RLinkRustcVersionMismatch<'a> {
+    pub rustc_version: String,
+    pub current_version: &'a str,
+}
+
+#[derive(SessionDiagnostic)]
+#[diag(driver::rlink_no_a_file)]
+pub(crate) struct RlinkNotAFile;

compiler/rustc_error_messages/locales/en-US/driver.ftl

@@ -0,0 +1,11 @@
+driver_rlink_unable_to_read = failed to read rlink file: `{$err}`
+
+driver_rlink_wrong_file_type = The input does not look like a .rlink file
+
+driver_rlink_empty_version_number = The input does not contain version number
+
+driver_rlink_encoding_version_mismatch = .rlink file was produced with encoding version `{$version_array}`, but the current version is `{$rlink_version}`
+
+driver_rlink_rustc_version_mismatch = .rlink file was produced by rustc version `{$rustc_version}`, but the current version is `{$current_version}`
+
+driver_rlink_no_a_file = rlink must be a file

compiler/rustc_error_messages/src/lib.rs

@@ -36,6 +36,7 @@ fluent_messages! {
     borrowck => "../locales/en-US/borrowck.ftl",
     builtin_macros => "../locales/en-US/builtin_macros.ftl",
     const_eval => "../locales/en-US/const_eval.ftl",
+    driver => "../locales/en-US/driver.ftl",
     expand => "../locales/en-US/expand.ftl",
     interface => "../locales/en-US/interface.ftl",
     lint => "../locales/en-US/lint.ftl",