Reduce the amount of explicit FatalError.raise()

Instead use dcx.abort_if_error() or guar.raise_fatal() instead. These
guarantee that an error actually happened previously and thus we don't
silently abort.

Author: bjorn3

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -15,7 +15,7 @@ use rustc_ast::CRATE_NODE_ID;
 use rustc_data_structures::fx::{FxIndexMap, FxIndexSet};
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::temp_dir::MaybeTempDir;
-use rustc_errors::{DiagCtxtHandle, FatalError};
+use rustc_errors::DiagCtxtHandle;
 use rustc_fs_util::{fix_windows_verbatim_for_gcc, try_canonicalize};
 use rustc_hir::def_id::{CrateNum, LOCAL_CRATE};
 use rustc_metadata::fs::{METADATA_FILENAME, copy_to_stdout, emit_wrapper_file};
@@ -1039,22 +1039,22 @@ fn link_natively(
         Err(e) => {
             let linker_not_found = e.kind() == io::ErrorKind::NotFound;
 
-            if linker_not_found {
-                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e });
+            let err = if linker_not_found {
+                sess.dcx().emit_err(errors::LinkerNotFound { linker_path, error: e })
             } else {
                 sess.dcx().emit_err(errors::UnableToExeLinker {
                     linker_path,
                     error: e,
                     command_formatted: format!("{cmd:?}"),
-                });
-            }
+                })
+            };
 
             if sess.target.is_like_msvc && linker_not_found {
                 sess.dcx().emit_note(errors::MsvcMissingLinker);
                 sess.dcx().emit_note(errors::CheckInstalledVisualStudio);
                 sess.dcx().emit_note(errors::InsufficientVSCodeProduct);
             }
-            FatalError.raise();
+            err.raise_fatal();
         }
     }
 

compiler/rustc_driver_impl/src/pretty.rs

@@ -4,7 +4,6 @@ use std::cell::Cell;
 use std::fmt::Write;
 
 use rustc_ast_pretty::pprust as pprust_ast;
-use rustc_errors::FatalError;
 use rustc_middle::bug;
 use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
 use rustc_middle::ty::{self, TyCtxt};
@@ -311,9 +310,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR tree");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_tree(did));
@@ -324,9 +321,7 @@ pub fn print<'tcx>(sess: &Session, ppm: PpMode, ex: PrintExtra<'tcx>) {
             let tcx = ex.tcx();
             let mut out = String::new();
             rustc_hir_analysis::check_crate(tcx);
-            if tcx.dcx().has_errors().is_some() {
-                FatalError.raise();
-            }
+            tcx.dcx().abort_if_errors();
             debug!("pretty printing THIR flat");
             for did in tcx.hir().body_owners() {
                 let _ = writeln!(out, "{:?}:\n{}\n", did, tcx.thir_flat(did));

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -16,8 +16,8 @@ use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::sync::Lrc;
 use rustc_errors::{
-    Applicability, Diag, DiagCtxtHandle, ErrorGuaranteed, FatalError, PResult, Subdiagnostic,
-    Suggestions, pluralize,
+    Applicability, Diag, DiagCtxtHandle, ErrorGuaranteed, PResult, Subdiagnostic, Suggestions,
+    pluralize,
 };
 use rustc_session::errors::ExprParenthesesNeeded;
 use rustc_span::edit_distance::find_best_match_for_name;
@@ -3023,17 +3023,10 @@ impl<'a> Parser<'a> {
     }
 
     pub(super) fn recover_vcs_conflict_marker(&mut self) {
-        if let Err(err) = self.err_vcs_conflict_marker() {
-            err.emit();
-            FatalError.raise();
-        }
-    }
-
-    pub(crate) fn err_vcs_conflict_marker(&mut self) -> PResult<'a, ()> {
         // <<<<<<<
         let Some(start) = self.conflict_marker(&TokenKind::BinOp(token::Shl), &TokenKind::Lt)
         else {
-            return Ok(());
+            return;
         };
         let mut spans = Vec::with_capacity(3);
         spans.push(start);
@@ -3063,7 +3056,7 @@ impl<'a> Parser<'a> {
             self.bump();
         }
 
-        let mut err = self.dcx().struct_span_err(spans, "encountered diff marker");
+        let mut err = self.dcx().struct_span_fatal(spans, "encountered diff marker");
         match middlediff3 {
             // We're using diff3
             Some(middlediff3) => {
@@ -3106,7 +3099,7 @@ impl<'a> Parser<'a> {
              visit <https://git-scm.com/book/en/v2/Git-Tools-Advanced-Merging#_checking_out_conflicts>",
         );
 
-        Err(err)
+        err.emit();
     }
 
     /// Parse and throw away a parenthesized comma separated

compiler/rustc_parse/src/parser/path.rs

@@ -597,8 +597,7 @@ impl<'a> Parser<'a> {
                 // When encountering severely malformed code where there are several levels of
                 // nested unclosed angle args (`f::<f::<f::<f::<...`), we avoid severe O(n^2)
                 // behavior by bailing out earlier (#117080).
-                e.emit();
-                rustc_errors::FatalError.raise();
+                e.emit().raise_fatal();
             }
             Err(e) if is_first_invocation && self.unmatched_angle_bracket_count > 0 => {
                 self.angle_bracket_nesting -= 1;

compiler/rustc_session/src/output.rs

@@ -3,7 +3,6 @@
 use std::path::Path;
 
 use rustc_ast::{self as ast, attr};
-use rustc_errors::FatalError;
 use rustc_span::{Span, Symbol, sym};
 
 use crate::Session;
@@ -90,11 +89,10 @@ pub fn find_crate_name(sess: &Session, attrs: &[ast::Attribute]) -> Symbol {
 }
 
 pub fn validate_crate_name(sess: &Session, s: Symbol, sp: Option<Span>) {
-    let mut err_count = 0;
+    let mut guar = None;
     {
         if s.is_empty() {
-            err_count += 1;
-            sess.dcx().emit_err(CrateNameEmpty { span: sp });
+            guar = Some(sess.dcx().emit_err(CrateNameEmpty { span: sp }));
         }
         for c in s.as_str().chars() {
             if c.is_alphanumeric() {
@@ -103,8 +101,7 @@ pub fn validate_crate_name(sess: &Session, s: Symbol, sp: Option<Span>) {
             if c == '_' {
                 continue;
             }
-            err_count += 1;
-            sess.dcx().emit_err(InvalidCharacterInCrateName {
+            guar = Some(sess.dcx().emit_err(InvalidCharacterInCrateName {
                 span: sp,
                 character: c,
                 crate_name: s,
@@ -113,12 +110,12 @@ pub fn validate_crate_name(sess: &Session, s: Symbol, sp: Option<Span>) {
                 } else {
                     None
                 },
-            });
+            }));
         }
     }
 
-    if err_count > 0 {
-        FatalError.raise();
+    if let Some(guar) = guar {
+        guar.raise_fatal();
     }
 }
 

compiler/rustc_trait_selection/src/error_reporting/traits/overflow.rs

@@ -1,8 +1,6 @@
 use std::fmt;
 
-use rustc_errors::{
-    Diag, E0275, EmissionGuarantee, ErrorGuaranteed, FatalError, struct_span_code_err,
-};
+use rustc_errors::{Diag, E0275, EmissionGuarantee, ErrorGuaranteed, struct_span_code_err};
 use rustc_hir::def::Namespace;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_infer::traits::{Obligation, PredicateObligation};
@@ -52,8 +50,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     ) -> ! {
         let mut err = self.build_overflow_error(cause, span, suggest_increasing_limit);
         mutate(&mut err);
-        err.emit();
-        FatalError.raise();
+        err.emit().raise_fatal();
     }
 
     pub fn build_overflow_error(