Auto merge of #93937 - bjorn3:simplifications3, r=cjgillot

Remove Config::stderr

1. It captured stdout and not stderr
2. It isn't used anywhere
3. All error messages should go to the DiagnosticOutput instead
4. It modifies thread local state

Marking as blocked as it will conflict a bit with #93936.

Author: bors

compiler/rustc_driver/src/lib.rs

@@ -226,7 +226,6 @@ fn run_compiler(
         output_dir: odir,
         file_loader,
         diagnostic_output,
-        stderr: None,
         lint_caps: Default::default(),
         parse_sess_created: None,
         register_lints: None,

compiler/rustc_interface/src/interface.rs

@@ -21,7 +21,6 @@ use rustc_session::{DiagnosticOutput, Session};
 use rustc_span::source_map::{FileLoader, FileName};
 use std::path::PathBuf;
 use std::result;
-use std::sync::{Arc, Mutex};
 
 pub type Result<T> = result::Result<T, ErrorReported>;
 
@@ -155,9 +154,6 @@ pub struct Config {
     pub file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
     pub diagnostic_output: DiagnosticOutput,
 
-    /// Set to capture stderr output during compiler execution
-    pub stderr: Option<Arc<Mutex<Vec<u8>>>>,
-
     pub lint_caps: FxHashMap<lint::LintId, lint::Level>,
 
     /// This is a callback from the driver that is called when [`ParseSess`] is created.
@@ -237,13 +233,11 @@ pub fn create_compiler_and_run<R>(config: Config, f: impl FnOnce(&Compiler) -> R
     })
 }
 
-pub fn run_compiler<R: Send>(mut config: Config, f: impl FnOnce(&Compiler) -> R + Send) -> R {
+pub fn run_compiler<R: Send>(config: Config, f: impl FnOnce(&Compiler) -> R + Send) -> R {
     tracing::trace!("run_compiler");
-    let stderr = config.stderr.take();
     util::run_in_thread_pool_with_globals(
         config.opts.edition,
         config.opts.debugging_opts.threads,
-        &stderr,
         || create_compiler_and_run(config, f),
     )
 }

compiler/rustc_interface/src/util.rs

@@ -27,15 +27,13 @@ use rustc_span::symbol::{sym, Symbol};
 use smallvec::SmallVec;
 use std::env;
 use std::env::consts::{DLL_PREFIX, DLL_SUFFIX};
-use std::io;
 use std::lazy::SyncOnceCell;
 use std::mem;
 use std::ops::DerefMut;
 #[cfg(not(parallel_compiler))]
 use std::panic;
 use std::path::{Path, PathBuf};
 use std::sync::atomic::{AtomicBool, Ordering};
-use std::sync::{Arc, Mutex};
 use std::thread;
 use tracing::info;
 
@@ -131,7 +129,6 @@ fn scoped_thread<F: FnOnce() -> R + Send, R: Send>(cfg: thread::Builder, f: F) -
 pub fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
     edition: Edition,
     _threads: usize,
-    stderr: &Option<Arc<Mutex<Vec<u8>>>>,
     f: F,
 ) -> R {
     let mut cfg = thread::Builder::new().name("rustc".to_string());
@@ -140,12 +137,7 @@ pub fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
         cfg = cfg.stack_size(size);
     }
 
-    let main_handler = move || {
-        rustc_span::create_session_globals_then(edition, || {
-            io::set_output_capture(stderr.clone());
-            f()
-        })
-    };
+    let main_handler = move || rustc_span::create_session_globals_then(edition, f);
 
     scoped_thread(cfg, main_handler)
 }
@@ -177,7 +169,6 @@ unsafe fn handle_deadlock() {
 pub fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
     edition: Edition,
     threads: usize,
-    stderr: &Option<Arc<Mutex<Vec<u8>>>>,
     f: F,
 ) -> R {
     let mut config = rayon::ThreadPoolBuilder::new()
@@ -199,10 +190,7 @@ pub fn run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
             // the thread local rustc uses. `session_globals` is captured and set
             // on the new threads.
             let main_handler = move |thread: rayon::ThreadBuilder| {
-                rustc_span::set_session_globals_then(session_globals, || {
-                    io::set_output_capture(stderr.clone());
-                    thread.run()
-                })
+                rustc_span::set_session_globals_then(session_globals, || thread.run())
             };
 
             config.build_scoped(main_handler, with_pool).unwrap()
@@ -339,6 +327,7 @@ fn sysroot_candidates() -> Vec<PathBuf> {
     #[cfg(windows)]
     fn current_dll_path() -> Option<PathBuf> {
         use std::ffi::OsString;
+        use std::io;
         use std::os::windows::prelude::*;
         use std::ptr;
 

src/librustdoc/core.rs

@@ -256,7 +256,6 @@ crate fn create_config(
         output_dir: None,
         file_loader: None,
         diagnostic_output: DiagnosticOutput::Default,
-        stderr: None,
         lint_caps,
         parse_sess_created: None,
         register_lints: Some(box crate::lint::register_lints),

src/librustdoc/doctest.rs

@@ -97,7 +97,6 @@ crate fn run(options: RustdocOptions) -> Result<(), ErrorReported> {
         output_dir: None,
         file_loader: None,
         diagnostic_output: DiagnosticOutput::Default,
-        stderr: None,
         lint_caps,
         parse_sess_created: None,
         register_lints: Some(box crate::lint::register_lints),

src/librustdoc/lib.rs

@@ -691,7 +691,6 @@ fn main_args(at_args: &[String]) -> MainResult {
     rustc_interface::util::run_in_thread_pool_with_globals(
         options.edition,
         1, // this runs single-threaded, even in a parallel compiler
-        &None,
         move || main_options(options),
     )
 }

src/test/run-make-fulldeps/issue-19371/foo.rs

@@ -55,7 +55,6 @@ fn compile(code: String, output: PathBuf, sysroot: PathBuf) {
         output_dir: None,
         file_loader: None,
         diagnostic_output: DiagnosticOutput::Default,
-        stderr: None,
         lint_caps: Default::default(),
         parse_sess_created: None,
         register_lints: None,