Remove SPAN_DEBUG global

The only difference between the default and rustc_interface set version
is that the default accesses the source map from SESSION_GLOBALS while
the rustc_interface version accesses the source map from the global
TyCtxt. SESSION_GLOBALS is always set while running the compiler while
the global TyCtxt is not always set. If the global TyCtxt is set, it's
source map is identical to the one in SESSION_GLOBALS

1 files changed, 1 insertions, 14 deletions

diff --git a/compiler/rustc_interface/src/callbacks.rs b/compiler/rustc_interface/src/callbacks.rs
index 3c7908fae79..a18e2d1d638 100644
--- a/compiler/rustc_interface/src/callbacks.rs
+++ b/compiler/rustc_interface/src/callbacks.rs
@@ -4,7 +4,7 @@
 //! `rustc_data_structures::AtomicRef` type, which allows us to setup a global
 //! static which can then be set in this file at program startup.
 //!
-//! See `SPAN_DEBUG` for an example of how to set things up.
+//! See `SPAN_TRACK` for an example of how to set things up.
 //!
 //! The functions in this file should fall back to the default set in their
 //! origin crate when the `TyCtxt` is not present in TLS.
@@ -13,18 +13,6 @@ use rustc_errors::{Diagnostic, TRACK_DIAGNOSTICS};
 use rustc_middle::ty::tls;
 use std::fmt;
 
-/// This is a callback from `rustc_ast` as it cannot access the implicit state
-/// in `rustc_middle` otherwise.
-fn span_debug(span: rustc_span::Span, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-    tls::with_opt(|tcx| {
-        if let Some(tcx) = tcx {
-            rustc_span::debug_with_source_map(span, f, tcx.sess.source_map())
-        } else {
-            rustc_span::default_span_debug(span, f)
-        }
-    })
-}
-
 fn track_span_parent(def_id: rustc_span::def_id::LocalDefId) {
     tls::with_opt(|tcx| {
         if let Some(tcx) = tcx {
@@ -65,7 +53,6 @@ fn def_id_debug(def_id: rustc_hir::def_id::DefId, f: &mut fmt::Formatter<'_>) ->
 /// Sets up the callbacks in prior crates which we want to refer to the
 /// TyCtxt in.
 pub fn setup_callbacks() {
-    rustc_span::SPAN_DEBUG.swap(&(span_debug as fn(_, &mut fmt::Formatter<'_>) -> _));
     rustc_span::SPAN_TRACK.swap(&(track_span_parent as fn(_)));
     rustc_hir::def_id::DEF_ID_DEBUG.swap(&(def_id_debug as fn(_, &mut fmt::Formatter<'_>) -> _));
     TRACK_DIAGNOSTICS.swap(&(track_diagnostic as fn(&_)));