Remove #[macro_use] extern crate tracing from rustc_middle.

Author: nnethercote

compiler/rustc_middle/src/hooks/mod.rs

@@ -10,6 +10,7 @@ use rustc_hir::def_id::{DefId, DefPathHash};
 use rustc_session::StableCrateId;
 use rustc_span::def_id::{CrateNum, LocalDefId};
 use rustc_span::{ExpnHash, ExpnId, DUMMY_SP};
+use tracing::instrument;
 
 macro_rules! declare_hooks {
     ($($(#[$attr:meta])*hook $name:ident($($arg:ident: $K:ty),*) -> $V:ty;)*) => {

compiler/rustc_middle/src/lib.rs

@@ -63,9 +63,6 @@
 #![feature(yeet_expr)]
 // tidy-alphabetical-end
 
-#[macro_use]
-extern crate tracing;
-
 #[cfg(test)]
 mod tests;
 

compiler/rustc_middle/src/lint.rs

@@ -12,6 +12,7 @@ use rustc_session::lint::{
 use rustc_session::Session;
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use rustc_span::{symbol, DesugaringKind, Span, Symbol, DUMMY_SP};
+use tracing::instrument;
 
 use crate::ty::TyCtxt;
 

compiler/rustc_middle/src/middle/region.rs

@@ -13,6 +13,7 @@ use rustc_hir as hir;
 use rustc_hir::{HirId, HirIdMap, Node};
 use rustc_macros::{HashStable, TyDecodable, TyEncodable};
 use rustc_span::{Span, DUMMY_SP};
+use tracing::debug;
 
 use std::fmt;
 use std::ops::Deref;

compiler/rustc_middle/src/middle/stability.rs

@@ -23,6 +23,7 @@ use rustc_session::Session;
 use rustc_span::symbol::{sym, Symbol};
 use rustc_span::Span;
 use std::num::NonZero;
+use tracing::debug;
 
 #[derive(PartialEq, Clone, Copy, Debug)]
 pub enum StabilityLevel {

compiler/rustc_middle/src/mir/interpret/allocation/provenance_map.rs

@@ -3,12 +3,12 @@
 
 use std::cmp;
 
+use super::{alloc_range, AllocError, AllocRange, AllocResult, CtfeProvenance, Provenance};
 use rustc_data_structures::sorted_map::SortedMap;
 use rustc_macros::HashStable;
-use rustc_target::abi::{HasDataLayout, Size};
-
-use super::{alloc_range, AllocError, AllocRange, AllocResult, CtfeProvenance, Provenance};
 use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
+use rustc_target::abi::{HasDataLayout, Size};
+use tracing::trace;
 
 /// Stores the provenance information of pointers stored in memory.
 #[derive(Clone, PartialEq, Eq, Hash, Debug)]

compiler/rustc_middle/src/mir/interpret/mod.rs

@@ -15,6 +15,7 @@ use std::num::NonZero;
 use std::sync::atomic::{AtomicU32, Ordering};
 
 use smallvec::{smallvec, SmallVec};
+use tracing::{debug, trace};
 
 use rustc_ast::LitKind;
 use rustc_data_structures::fx::FxHashMap;

compiler/rustc_middle/src/mir/interpret/queries.rs

@@ -9,6 +9,7 @@ use rustc_hir::def::DefKind;
 use rustc_hir::def_id::DefId;
 use rustc_session::lint;
 use rustc_span::{Span, DUMMY_SP};
+use tracing::{debug, instrument};
 
 impl<'tcx> TyCtxt<'tcx> {
     /// Evaluates a constant without providing any generic parameters. This is useful to evaluate consts

compiler/rustc_middle/src/mir/mod.rs

@@ -37,6 +37,7 @@ use rustc_span::symbol::Symbol;
 use rustc_span::{Span, DUMMY_SP};
 
 use either::Either;
+use tracing::trace;
 
 use std::borrow::Cow;
 use std::cell::RefCell;

compiler/rustc_middle/src/mir/mono.rs

@@ -18,6 +18,7 @@ use rustc_span::symbol::Symbol;
 use rustc_span::Span;
 use std::fmt;
 use std::hash::Hash;
+use tracing::debug;
 
 /// Describes how a monomorphization will be instantiated in object files.
 #[derive(PartialEq)]