Always import all tracing macros for the entire crate instead of piecemeal by module

compiler/rustc_session/src/cgu_reuse_tracker.rs

@@ -10,7 +10,6 @@ use rustc_span::{Span, Symbol};
 use std::borrow::Cow;
 use std::fmt::{self};
 use std::sync::{Arc, Mutex};
-use tracing::debug;
 
 #[derive(Copy, Clone, Debug, PartialEq, PartialOrd)]
 pub enum CguReuse {

compiler/rustc_session/src/config.rs

@@ -2530,7 +2530,7 @@ fn parse_pretty(unstable_opts: &UnstableOptions, efmt: ErrorOutputType) -> Optio
             ),
         ),
     };
-    tracing::debug!("got unpretty option: {first:?}");
+    debug!("got unpretty option: {first:?}");
     Some(first)
 }
 

compiler/rustc_session/src/filesearch.rs

@@ -7,7 +7,6 @@ use std::path::{Path, PathBuf};
 
 use crate::search_paths::{PathKind, SearchPath};
 use rustc_fs_util::fix_windows_verbatim_for_gcc;
-use tracing::debug;
 
 #[derive(Copy, Clone)]
 pub enum FileMatch {

compiler/rustc_session/src/lib.rs

@@ -14,6 +14,9 @@
 extern crate rustc_macros;
 pub mod errors;
 
+#[macro_use]
+extern crate tracing;
+
 pub mod cgu_reuse_tracker;
 pub mod utils;
 pub use lint::{declare_lint, declare_lint_pass, declare_tool_lint, impl_lint_pass};