Remove reached_eof from ParseSess

It was only ever set in a function which isn't called anywhere.

compiler/rustc_parse/src/lexer/mod.rs

@@ -74,7 +74,6 @@ pub(crate) fn parse_token_trees<'a>(
             // because the delimiter mismatch is more likely to be the root cause of error
 
             let mut buffer = Vec::with_capacity(1);
-            // Not using `emit_unclosed_delims` to use `db.buffer`
             for unmatched in unmatched_delims {
                 if let Some(err) = make_unclosed_delims_error(unmatched, &sess) {
                     err.buffer(&mut buffer);

compiler/rustc_parse/src/parser/mod.rs

@@ -29,7 +29,6 @@
 use rustc_ast::{HasAttrs, HasTokens, Unsafe, Visibility, VisibilityKind};
 use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
-use rustc_data_structures::sync::Ordering;
 use rustc_errors::PResult;
 use rustc_errors::{
     Applicability, DiagnosticBuilder, ErrorGuaranteed, FatalError, IntoDiagnostic, MultiSpan,
@@ -1455,18 +1454,6 @@ pub(crate) fn make_unclosed_delims_error(
     Some(err)
 }
 
-pub fn emit_unclosed_delims(unclosed_delims: &mut Vec<UnmatchedDelim>, sess: &ParseSess) {
-    let _ = sess.reached_eof.fetch_or(
-        unclosed_delims.iter().any(|unmatched_delim| unmatched_delim.found_delim.is_none()),
-        Ordering::Relaxed,
-    );
-    for unmatched in unclosed_delims.drain(..) {
-        if let Some(mut e) = make_unclosed_delims_error(unmatched, sess) {
-            e.emit();
-        }
-    }
-}
-
 /// A helper struct used when building an `AttrTokenStream` from
 /// a `LazyAttrTokenStream`. Both delimiter and non-delimited tokens
 /// are stored as `FlatToken::Token`. A vector of `FlatToken`s

compiler/rustc_passes/src/entry.rs

@@ -187,12 +187,6 @@ fn sigpipe(tcx: TyCtxt<'_>, def_id: DefId) -> u8 {
 
 fn no_main_err(tcx: TyCtxt<'_>, visitor: &EntryContext<'_>) {
     let sp = tcx.def_span(CRATE_DEF_ID);
-    if tcx.sess.parse_sess.reached_eof.load(rustc_data_structures::sync::Ordering::Relaxed) {
-        // There's an unclosed brace that made the parser reach `Eof`, we shouldn't complain about
-        // the missing `fn main()` then as it might have been hidden inside an unclosed block.
-        tcx.sess.delay_span_bug(sp, "`main` not found, but expected unclosed brace error");
-        return;
-    }
 
     // There is no main function.
     let mut has_filename = true;

compiler/rustc_session/src/parse.rs

@@ -8,7 +8,7 @@
 };
 use rustc_ast::node_id::NodeId;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexSet};
-use rustc_data_structures::sync::{AppendOnlyVec, AtomicBool, Lock, Lrc};
+use rustc_data_structures::sync::{AppendOnlyVec, Lock, Lrc};
 use rustc_errors::{emitter::SilentEmitter, Handler};
 use rustc_errors::{
     fallback_fluent_bundle, Diagnostic, DiagnosticBuilder, DiagnosticId, DiagnosticMessage,
@@ -204,8 +204,6 @@ pub struct ParseSess {
     pub ambiguous_block_expr_parse: Lock<FxHashMap<Span, Span>>,
     pub gated_spans: GatedSpans,
     pub symbol_gallery: SymbolGallery,
-    /// The parser has reached `Eof` due to an unclosed brace. Used to silence unnecessary errors.
-    pub reached_eof: AtomicBool,
     /// Environment variables accessed during the build and their values when they exist.
     pub env_depinfo: Lock<FxHashSet<(Symbol, Option<Symbol>)>>,
     /// File paths accessed during the build.
@@ -242,7 +240,6 @@ pub fn with_span_handler(handler: Handler, source_map: Lrc<SourceMap>) -> Self {
             ambiguous_block_expr_parse: Lock::new(FxHashMap::default()),
             gated_spans: GatedSpans::default(),
             symbol_gallery: SymbolGallery::default(),
-            reached_eof: AtomicBool::new(false),
             env_depinfo: Default::default(),
             file_depinfo: Default::default(),
             assume_incomplete_release: false,