Code change:
let attrs = self.parse_outer_attributes()?; let lo = self.token.span; <del> Ok(Some(if self.eat_keyword(kw::Let) { Stmt { id: DUMMY_NODE_ID, kind: StmtKind::Local(self.parse_local(attrs.into())?), span: lo.to(self.prev_span), } } else if let Some(macro_def) = self.eat_macro_def( &attrs, &respan(lo, VisibilityKind::Inherited), lo, )? { Stmt { id: DUMMY_NODE_ID, kind: StmtKind::Item(macro_def), span: lo.to(self.prev_span), } </del> <ins> if self.eat_keyword(kw::Let) { let local = self.parse_local(attrs.into())?; return Ok(Some(self.mk_stmt(lo.to(self.prev_span), StmtKind::Local(local)))); } let mac_vis = respan(lo, VisibilityKind::Inherited); if let Some(macro_def) = self.eat_macro_def(&attrs, &mac_vis, lo)? { return Ok(Some(self.mk_stmt(lo.to(self.prev_span), StmtKind::Item(macro_def)))); } </ins> // Starts like a simple path, being careful to avoid contextual keywords // such as a union items, item with `crate` visibility or auto trait items. // Our goal here is to parse an arbitrary path `a::b::c` but not something that starts // like a path (1 token), but it fact not a path. <del> // `union::b::c` - path, `union U { ... }` - not a path. // `crate::b::c` - path, `crate struct S;` - not a path. } else if self.token.is_path_start() && !self.token.is_qpath_start() && !self.is_union_item() && !self.is_crate_vis() && !self.is_auto_trait_item() && !self.is_async_fn() { </del> <ins> if self.token.is_path_start() && !self.token.is_qpath_start() && !self.is_union_item() // `union::b::c` - path, `union U { ... }` - not a path. && !self.is_crate_vis() // `crate::b::c` - path, `crate struct S;` - not a path. && !self.is_auto_trait_item() && !self.is_async_fn() { </ins> let path = self.parse_path(PathStyle::Expr)?; <del> if !self.eat(&token::Not) { let expr = if self.check(&token::OpenDelim(token::Brace)) { self.parse_struct_expr(lo, path, ThinVec::new())? } else { let hi = self.prev_span; self.mk_expr(lo.to(hi), ExprKind::Path(None, path), ThinVec::new()) }; let expr = self.with_res(Restrictions::STMT_EXPR, |this| { let expr = this.parse_dot_or_call_expr_with(expr, lo, attrs.into())?; this.parse_assoc_expr_with(0, LhsExpr::AlreadyParsed(expr)) })?; return Ok(Some(Stmt { id: DUMMY_NODE_ID, kind: StmtKind::Expr(expr), span: lo.to(self.prev_span), })); </del> <ins> if self.eat(&token::Not) { return self.parse_stmt_mac(lo, attrs.into(), path, macro_legacy_warnings); </ins> } <del> let args = self.parse_mac_args()?; let delim = args.delim(); let hi = self.prev_span; let style = if delim == token::Brace { MacStmtStyle::Braces </del> <ins> let expr = if self.check(&token::OpenDelim(token::Brace)) { self.parse_struct_expr(lo, path, ThinVec::new())? </ins> } else { <del> MacStmtStyle::NoBraces </del> <ins> let hi = self.prev_span; self.mk_expr(lo.to(hi), ExprKind::Path(None, path), ThinVec::new()) </ins> }; <del> let mac = Mac { path, args, prior_type_ascription: self.last_type_ascription, }; let kind = if delim == token::Brace || self.token == token::Semi || self.token == token::Eof { StmtKind::Mac(P((mac, style, attrs.into()))) } // We used to incorrectly stop parsing macro-expanded statements here. // If the next token will be an error anyway but could have parsed with the // earlier behavior, stop parsing here and emit a warning to avoid breakage. else if macro_legacy_warnings && self.token.can_begin_expr() && match self.token.kind { // These can continue an expression, so we can't stop parsing and warn. token::OpenDelim(token::Paren) | token::OpenDelim(token::Bracket) | token::BinOp(token::Minus) | token::BinOp(token::Star) | token::BinOp(token::And) | token::BinOp(token::Or) | token::AndAnd | token::OrOr | token::DotDot | token::DotDotDot | token::DotDotEq => false, _ => true, } { self.warn_missing_semicolon(); StmtKind::Mac(P((mac, style, attrs.into()))) } else { let e = self.mk_expr(lo.to(hi), ExprKind::Mac(mac), ThinVec::new()); let e = self.maybe_recover_from_bad_qpath(e, true)?; let e = self.parse_dot_or_call_expr_with(e, lo, attrs.into())?; let e = self.parse_assoc_expr_with(0, LhsExpr::AlreadyParsed(e))?; StmtKind::Expr(e) }; Stmt { id: DUMMY_NODE_ID, span: lo.to(hi), kind, </del> <ins> let expr = self.with_res(Restrictions::STMT_EXPR, |this| { let expr = this.parse_dot_or_call_expr_with(expr, lo, attrs.into())?; this.parse_assoc_expr_with(0, LhsExpr::AlreadyParsed(expr)) })?; return Ok(Some(self.mk_stmt(lo.to(self.prev_span), StmtKind::Expr(expr)))); } // FIXME: Bad copy of attrs let old_directory_ownership = mem::replace(&mut self.directory.ownership, DirectoryOwnership::UnownedViaBlock); let item = self.parse_item_(attrs.clone(), false, true)?; self.directory.ownership = old_directory_ownership; if let Some(item) = item { return Ok(Some(self.mk_stmt(lo.to(item.span), StmtKind::Item(item)))); } // Do not attempt to parse an expression if we're done here. if self.token == token::Semi { self.error_outer_attrs(&attrs); self.bump(); let mut last_semi = lo; while self.token == token::Semi { last_semi = self.token.span; self.bump(); </ins> } <ins> // We are encoding a string of semicolons as an an empty tuple that spans // the excess semicolons to preserve this info until the lint stage. let kind = StmtKind::Semi(self.mk_expr( lo.to(last_semi), ExprKind::Tup(Vec::new()), ThinVec::new() )); return Ok(Some(self.mk_stmt(lo.to(last_semi), kind))); } if self.token == token::CloseDelim(token::Brace) { self.error_outer_attrs(&attrs); return Ok(None); } // Remainder are line-expr stmts. let e = self.parse_expr_res(Restrictions::STMT_EXPR, Some(attrs.into()))?; Ok(Some(self.mk_stmt(lo.to(e.span), StmtKind::Expr(e)))) } /// Parses a statement macro `mac!(args)` provided a `path` representing `mac`. /// At this point, the `!` token after the path has already been eaten. fn parse_stmt_mac( &mut self, lo: Span, attrs: ThinVec<Attribute>, path: ast::Path, legacy_warnings: bool, ) -> PResult<'a, Option<Stmt>> { let args = self.parse_mac_args()?; let delim = args.delim(); let hi = self.prev_span; let style = if delim == token::Brace { MacStmtStyle::Braces </ins> } else { <del> // FIXME: Bad copy of attrs let old_directory_ownership = mem::replace(&mut self.directory.ownership, DirectoryOwnership::UnownedViaBlock); let item = self.parse_item_(attrs.clone(), false, true)?; self.directory.ownership = old_directory_ownership; match item { Some(i) => Stmt { id: DUMMY_NODE_ID, span: lo.to(i.span), kind: StmtKind::Item(i), }, None => { let unused_attrs = |attrs: &[Attribute], s: &mut Self| { if !attrs.is_empty() { if s.prev_token_kind == PrevTokenKind::DocComment { s.span_fatal_err(s.prev_span, Error::UselessDocComment).emit(); } else if attrs.iter().any(|a| a.style == AttrStyle::Outer) { s.span_err( s.token.span, "expected statement after outer attribute" ); } } }; // Do not attempt to parse an expression if we're done here. if self.token == token::Semi { unused_attrs(&attrs, self); self.bump(); let mut last_semi = lo; while self.token == token::Semi { last_semi = self.token.span; self.bump(); } // We are encoding a string of semicolons as an // an empty tuple that spans the excess semicolons // to preserve this info until the lint stage return Ok(Some(Stmt { id: DUMMY_NODE_ID, span: lo.to(last_semi), kind: StmtKind::Semi(self.mk_expr(lo.to(last_semi), ExprKind::Tup(Vec::new()), ThinVec::new() )), })); } </del> <ins> MacStmtStyle::NoBraces }; </ins> <del> if self.token == token::CloseDelim(token::Brace) { unused_attrs(&attrs, self); return Ok(None); } </del> <ins> let mac = Mac { path, args, prior_type_ascription: self.last_type_ascription, }; </ins> <del> // Remainder are line-expr stmts. let e = self.parse_expr_res( Restrictions::STMT_EXPR, Some(attrs.into()))?; Stmt { id: DUMMY_NODE_ID, span: lo.to(e.span), kind: StmtKind::Expr(e), } } </del> <ins> let kind = if delim == token::Brace || self.token == token::Semi || self.token == token::Eof { StmtKind::Mac(P((mac, style, attrs.into()))) } // We used to incorrectly stop parsing macro-expanded statements here. // If the next token will be an error anyway but could have parsed with the // earlier behavior, stop parsing here and emit a warning to avoid breakage. else if legacy_warnings && self.token.can_begin_expr() && match self.token.kind { // These can continue an expression, so we can't stop parsing and warn. token::OpenDelim(token::Paren) | token::OpenDelim(token::Bracket) | token::BinOp(token::Minus) | token::BinOp(token::Star) | token::BinOp(token::And) | token::BinOp(token::Or) | token::AndAnd | token::OrOr | token::DotDot | token::DotDotDot | token::DotDotEq => false, _ => true, </ins> } <del> })) </del> <ins> { self.warn_missing_semicolon(); StmtKind::Mac(P((mac, style, attrs))) } else { // Since none of the above applied, this is an expression statement macro. let e = self.mk_expr(lo.to(hi), ExprKind::Mac(mac), ThinVec::new()); let e = self.maybe_recover_from_bad_qpath(e, true)?; let e = self.parse_dot_or_call_expr_with(e, lo, attrs)?; let e = self.parse_assoc_expr_with(0, LhsExpr::AlreadyParsed(e))?; StmtKind::Expr(e) }; Ok(Some(self.mk_stmt(lo.to(hi), kind))) } /// Error on outer attributes in this context. /// Also error if the previous token was a doc comment. fn error_outer_attrs(&self, attrs: &[Attribute]) { if !attrs.is_empty() { if self.prev_token_kind == PrevTokenKind::DocComment { self.span_fatal_err(self.prev_span, Error::UselessDocComment).emit(); } else if attrs.iter().any(|a| a.style == AttrStyle::Outer) { self.span_err(self.token.span, "expected statement after outer attribute"); } } </ins> } /// Parses a local variable declaration.

Related discussion:
text: From The following code should be using the common list parsing utilities: CC
What/where are the common list parsing utilties? Edit: never mind, I've got it. , , etc. for anyone who's wondering.