diff --git a/compiler/rustc_mir_transform/src/coverage/spans.rs b/compiler/rustc_mir_transform/src/coverage/spans.rs index 35cf9ea5f91cd..deebf5345bac9 100644 --- a/compiler/rustc_mir_transform/src/coverage/spans.rs +++ b/compiler/rustc_mir_transform/src/coverage/spans.rs @@ -11,7 +11,7 @@ use rustc_middle::ty::TyCtxt; use rustc_span::source_map::original_sp; use rustc_span::{BytePos, ExpnKind, MacroKind, Span, Symbol}; -use std::cell::RefCell; +use std::cell::OnceCell; use std::cmp::Ordering; #[derive(Debug, Copy, Clone)] @@ -67,7 +67,7 @@ impl CoverageStatement { pub(super) struct CoverageSpan { pub span: Span, pub expn_span: Span, - pub current_macro_or_none: RefCell>>, + pub current_macro_or_none: OnceCell>, pub bcb: BasicCoverageBlock, pub coverage_statements: Vec, pub is_closure: bool, @@ -175,8 +175,7 @@ impl CoverageSpan { /// If the span is part of a macro, returns the macro name symbol. pub fn current_macro(&self) -> Option { self.current_macro_or_none - .borrow_mut() - .get_or_insert_with(|| { + .get_or_init(|| { if let ExpnKind::Macro(MacroKind::Bang, current_macro) = self.expn_span.ctxt().outer_expn_data().kind {