mirror of
https://github.com/rust-lang/rust.git
synced 2025-10-30 20:44:34 +00:00
771 lines
28 KiB
Rust
771 lines
28 KiB
Rust
use rustc_ast::mut_visit::{visit_clobber, MutVisitor, *};
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use rustc_ast::ptr::P;
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use rustc_ast::util::lev_distance::find_best_match_for_name;
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use rustc_ast::{self as ast, AttrVec, BlockCheckMode};
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use rustc_codegen_ssa::traits::CodegenBackend;
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use rustc_data_structures::fingerprint::Fingerprint;
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use rustc_data_structures::fx::{FxHashMap, FxHashSet};
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#[cfg(parallel_compiler)]
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use rustc_data_structures::jobserver;
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use rustc_data_structures::stable_hasher::StableHasher;
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use rustc_data_structures::sync::Lrc;
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use rustc_errors::registry::Registry;
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use rustc_metadata::dynamic_lib::DynamicLibrary;
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use rustc_resolve::{self, Resolver};
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use rustc_session as session;
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use rustc_session::config::{self, CrateType};
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use rustc_session::config::{ErrorOutputType, Input, OutputFilenames};
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use rustc_session::lint::{self, BuiltinLintDiagnostics, LintBuffer};
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use rustc_session::parse::CrateConfig;
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use rustc_session::CrateDisambiguator;
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use rustc_session::{early_error, filesearch, output, DiagnosticOutput, Session};
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use rustc_span::edition::Edition;
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use rustc_span::source_map::FileLoader;
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use rustc_span::symbol::{sym, Symbol};
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use smallvec::SmallVec;
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use std::env;
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use std::io::{self, Write};
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use std::mem;
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use std::ops::DerefMut;
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use std::path::{Path, PathBuf};
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use std::sync::{Arc, Mutex, Once};
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#[cfg(not(parallel_compiler))]
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use std::{panic, thread};
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use tracing::info;
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/// Adds `target_feature = "..."` cfgs for a variety of platform
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/// specific features (SSE, NEON etc.).
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///
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/// This is performed by checking whether a set of permitted features
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/// is available on the target machine, by querying LLVM.
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pub fn add_configuration(
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cfg: &mut CrateConfig,
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sess: &mut Session,
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codegen_backend: &dyn CodegenBackend,
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) {
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let tf = sym::target_feature;
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let target_features = codegen_backend.target_features(sess);
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sess.target_features.extend(target_features.iter().cloned());
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cfg.extend(target_features.into_iter().map(|feat| (tf, Some(feat))));
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if sess.crt_static(None) {
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cfg.insert((tf, Some(sym::crt_dash_static)));
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}
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}
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pub fn create_session(
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sopts: config::Options,
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cfg: FxHashSet<(String, Option<String>)>,
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diagnostic_output: DiagnosticOutput,
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file_loader: Option<Box<dyn FileLoader + Send + Sync + 'static>>,
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input_path: Option<PathBuf>,
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lint_caps: FxHashMap<lint::LintId, lint::Level>,
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descriptions: Registry,
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) -> (Lrc<Session>, Lrc<Box<dyn CodegenBackend>>) {
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let mut sess = session::build_session(
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sopts,
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input_path,
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descriptions,
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diagnostic_output,
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lint_caps,
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file_loader,
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);
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let codegen_backend = get_codegen_backend(&sess);
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let mut cfg = config::build_configuration(&sess, config::to_crate_config(cfg));
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add_configuration(&mut cfg, &mut sess, &*codegen_backend);
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sess.parse_sess.config = cfg;
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(Lrc::new(sess), Lrc::new(codegen_backend))
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}
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const STACK_SIZE: usize = 8 * 1024 * 1024;
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fn get_stack_size() -> Option<usize> {
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// FIXME: Hacks on hacks. If the env is trying to override the stack size
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// then *don't* set it explicitly.
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env::var_os("RUST_MIN_STACK").is_none().then_some(STACK_SIZE)
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}
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struct Sink(Arc<Mutex<Vec<u8>>>);
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impl Write for Sink {
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fn write(&mut self, data: &[u8]) -> io::Result<usize> {
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Write::write(&mut *self.0.lock().unwrap(), data)
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}
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fn flush(&mut self) -> io::Result<()> {
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Ok(())
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}
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}
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/// Like a `thread::Builder::spawn` followed by a `join()`, but avoids the need
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/// for `'static` bounds.
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#[cfg(not(parallel_compiler))]
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pub fn scoped_thread<F: FnOnce() -> R + Send, R: Send>(cfg: thread::Builder, f: F) -> R {
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struct Ptr(*mut ());
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unsafe impl Send for Ptr {}
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unsafe impl Sync for Ptr {}
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let mut f = Some(f);
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let run = Ptr(&mut f as *mut _ as *mut ());
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let mut result = None;
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let result_ptr = Ptr(&mut result as *mut _ as *mut ());
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let thread = cfg.spawn(move || {
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let run = unsafe { (*(run.0 as *mut Option<F>)).take().unwrap() };
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let result = unsafe { &mut *(result_ptr.0 as *mut Option<R>) };
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*result = Some(run());
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});
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match thread.unwrap().join() {
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Ok(()) => result.unwrap(),
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Err(p) => panic::resume_unwind(p),
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}
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}
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#[cfg(not(parallel_compiler))]
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pub fn setup_callbacks_and_run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
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edition: Edition,
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_threads: usize,
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stderr: &Option<Arc<Mutex<Vec<u8>>>>,
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f: F,
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) -> R {
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let mut cfg = thread::Builder::new().name("rustc".to_string());
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if let Some(size) = get_stack_size() {
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cfg = cfg.stack_size(size);
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}
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crate::callbacks::setup_callbacks();
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let main_handler = move || {
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rustc_span::with_session_globals(edition, || {
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if let Some(stderr) = stderr {
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io::set_panic(Some(box Sink(stderr.clone())));
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}
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f()
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})
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};
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scoped_thread(cfg, main_handler)
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}
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#[cfg(parallel_compiler)]
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pub fn setup_callbacks_and_run_in_thread_pool_with_globals<F: FnOnce() -> R + Send, R: Send>(
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edition: Edition,
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threads: usize,
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stderr: &Option<Arc<Mutex<Vec<u8>>>>,
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f: F,
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) -> R {
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use rustc_middle::ty;
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crate::callbacks::setup_callbacks();
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let mut config = rayon::ThreadPoolBuilder::new()
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.thread_name(|_| "rustc".to_string())
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.acquire_thread_handler(jobserver::acquire_thread)
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.release_thread_handler(jobserver::release_thread)
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.num_threads(threads)
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.deadlock_handler(|| unsafe { ty::query::handle_deadlock() });
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if let Some(size) = get_stack_size() {
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config = config.stack_size(size);
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}
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let with_pool = move |pool: &rayon::ThreadPool| pool.install(move || f());
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rustc_span::with_session_globals(edition, || {
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rustc_span::SESSION_GLOBALS.with(|session_globals| {
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// The main handler runs for each Rayon worker thread and sets up
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// the thread local rustc uses. `session_globals` is captured and set
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// on the new threads.
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let main_handler = move |thread: rayon::ThreadBuilder| {
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rustc_span::SESSION_GLOBALS.set(session_globals, || {
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if let Some(stderr) = stderr {
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io::set_panic(Some(box Sink(stderr.clone())));
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}
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thread.run()
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})
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};
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config.build_scoped(main_handler, with_pool).unwrap()
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})
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})
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}
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fn load_backend_from_dylib(path: &Path) -> fn() -> Box<dyn CodegenBackend> {
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let lib = DynamicLibrary::open(path).unwrap_or_else(|err| {
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let err = format!("couldn't load codegen backend {:?}: {:?}", path, err);
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early_error(ErrorOutputType::default(), &err);
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});
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unsafe {
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match lib.symbol("__rustc_codegen_backend") {
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Ok(f) => {
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mem::forget(lib);
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mem::transmute::<*mut u8, _>(f)
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}
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Err(e) => {
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let err = format!(
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"couldn't load codegen backend as it \
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doesn't export the `__rustc_codegen_backend` \
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symbol: {:?}",
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e
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);
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early_error(ErrorOutputType::default(), &err);
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}
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}
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}
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}
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pub fn get_codegen_backend(sess: &Session) -> Box<dyn CodegenBackend> {
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static INIT: Once = Once::new();
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static mut LOAD: fn() -> Box<dyn CodegenBackend> = || unreachable!();
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INIT.call_once(|| {
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let codegen_name = sess.opts.debugging_opts.codegen_backend.as_deref().unwrap_or("llvm");
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let backend = match codegen_name {
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filename if filename.contains('.') => load_backend_from_dylib(filename.as_ref()),
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codegen_name => get_builtin_codegen_backend(codegen_name),
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};
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unsafe {
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LOAD = backend;
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}
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});
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let backend = unsafe { LOAD() };
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backend.init(sess);
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backend
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}
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// This is used for rustdoc, but it uses similar machinery to codegen backend
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// loading, so we leave the code here. It is potentially useful for other tools
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// that want to invoke the rustc binary while linking to rustc as well.
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pub fn rustc_path<'a>() -> Option<&'a Path> {
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static RUSTC_PATH: once_cell::sync::OnceCell<Option<PathBuf>> =
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once_cell::sync::OnceCell::new();
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const BIN_PATH: &str = env!("RUSTC_INSTALL_BINDIR");
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RUSTC_PATH.get_or_init(|| get_rustc_path_inner(BIN_PATH)).as_ref().map(|v| &**v)
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}
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fn get_rustc_path_inner(bin_path: &str) -> Option<PathBuf> {
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sysroot_candidates().iter().find_map(|sysroot| {
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let candidate = sysroot.join(bin_path).join(if cfg!(target_os = "windows") {
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"rustc.exe"
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} else {
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"rustc"
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});
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candidate.exists().then_some(candidate)
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})
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}
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fn sysroot_candidates() -> Vec<PathBuf> {
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let target = session::config::host_triple();
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let mut sysroot_candidates = vec![filesearch::get_or_default_sysroot()];
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let path = current_dll_path().and_then(|s| s.canonicalize().ok());
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if let Some(dll) = path {
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// use `parent` twice to chop off the file name and then also the
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// directory containing the dll which should be either `lib` or `bin`.
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if let Some(path) = dll.parent().and_then(|p| p.parent()) {
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// The original `path` pointed at the `rustc_driver` crate's dll.
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// Now that dll should only be in one of two locations. The first is
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// in the compiler's libdir, for example `$sysroot/lib/*.dll`. The
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// other is the target's libdir, for example
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// `$sysroot/lib/rustlib/$target/lib/*.dll`.
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//
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// We don't know which, so let's assume that if our `path` above
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// ends in `$target` we *could* be in the target libdir, and always
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// assume that we may be in the main libdir.
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sysroot_candidates.push(path.to_owned());
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if path.ends_with(target) {
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sysroot_candidates.extend(
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path.parent() // chop off `$target`
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.and_then(|p| p.parent()) // chop off `rustlib`
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.and_then(|p| p.parent()) // chop off `lib`
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.map(|s| s.to_owned()),
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);
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}
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}
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}
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return sysroot_candidates;
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#[cfg(unix)]
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fn current_dll_path() -> Option<PathBuf> {
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use std::ffi::{CStr, OsStr};
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use std::os::unix::prelude::*;
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unsafe {
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let addr = current_dll_path as usize as *mut _;
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let mut info = mem::zeroed();
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if libc::dladdr(addr, &mut info) == 0 {
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info!("dladdr failed");
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return None;
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}
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if info.dli_fname.is_null() {
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info!("dladdr returned null pointer");
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return None;
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}
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let bytes = CStr::from_ptr(info.dli_fname).to_bytes();
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let os = OsStr::from_bytes(bytes);
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Some(PathBuf::from(os))
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}
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}
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#[cfg(windows)]
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fn current_dll_path() -> Option<PathBuf> {
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use std::ffi::OsString;
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use std::os::windows::prelude::*;
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use std::ptr;
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use winapi::um::libloaderapi::{
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GetModuleFileNameW, GetModuleHandleExW, GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
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};
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unsafe {
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let mut module = ptr::null_mut();
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let r = GetModuleHandleExW(
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GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS,
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current_dll_path as usize as *mut _,
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&mut module,
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);
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if r == 0 {
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info!("GetModuleHandleExW failed: {}", io::Error::last_os_error());
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return None;
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}
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let mut space = Vec::with_capacity(1024);
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let r = GetModuleFileNameW(module, space.as_mut_ptr(), space.capacity() as u32);
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if r == 0 {
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info!("GetModuleFileNameW failed: {}", io::Error::last_os_error());
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return None;
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}
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let r = r as usize;
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if r >= space.capacity() {
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info!("our buffer was too small? {}", io::Error::last_os_error());
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return None;
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}
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space.set_len(r);
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let os = OsString::from_wide(&space);
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Some(PathBuf::from(os))
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}
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}
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}
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pub fn get_builtin_codegen_backend(backend_name: &str) -> fn() -> Box<dyn CodegenBackend> {
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#[cfg(feature = "llvm")]
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{
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if backend_name == "llvm" {
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return rustc_codegen_llvm::LlvmCodegenBackend::new;
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}
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}
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let err = format!("unsupported builtin codegen backend `{}`", backend_name);
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early_error(ErrorOutputType::default(), &err);
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}
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pub(crate) fn compute_crate_disambiguator(session: &Session) -> CrateDisambiguator {
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use std::hash::Hasher;
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// The crate_disambiguator is a 128 bit hash. The disambiguator is fed
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// into various other hashes quite a bit (symbol hashes, incr. comp. hashes,
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// debuginfo type IDs, etc), so we don't want it to be too wide. 128 bits
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// should still be safe enough to avoid collisions in practice.
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let mut hasher = StableHasher::new();
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let mut metadata = session.opts.cg.metadata.clone();
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// We don't want the crate_disambiguator to dependent on the order
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// -C metadata arguments, so sort them:
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metadata.sort();
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// Every distinct -C metadata value is only incorporated once:
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metadata.dedup();
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hasher.write(b"metadata");
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for s in &metadata {
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// Also incorporate the length of a metadata string, so that we generate
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// different values for `-Cmetadata=ab -Cmetadata=c` and
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// `-Cmetadata=a -Cmetadata=bc`
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hasher.write_usize(s.len());
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hasher.write(s.as_bytes());
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}
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// Also incorporate crate type, so that we don't get symbol conflicts when
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// linking against a library of the same name, if this is an executable.
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let is_exe = session.crate_types().contains(&CrateType::Executable);
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hasher.write(if is_exe { b"exe" } else { b"lib" });
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CrateDisambiguator::from(hasher.finish::<Fingerprint>())
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}
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pub(crate) fn check_attr_crate_type(
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sess: &Session,
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attrs: &[ast::Attribute],
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lint_buffer: &mut LintBuffer,
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) {
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// Unconditionally collect crate types from attributes to make them used
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for a in attrs.iter() {
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if sess.check_name(a, sym::crate_type) {
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if let Some(n) = a.value_str() {
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if categorize_crate_type(n).is_some() {
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return;
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}
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if let ast::MetaItemKind::NameValue(spanned) = a.meta().unwrap().kind {
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let span = spanned.span;
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let lev_candidate =
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find_best_match_for_name(CRATE_TYPES.iter().map(|(k, _)| k), n, None);
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if let Some(candidate) = lev_candidate {
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lint_buffer.buffer_lint_with_diagnostic(
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lint::builtin::UNKNOWN_CRATE_TYPES,
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ast::CRATE_NODE_ID,
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span,
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"invalid `crate_type` value",
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BuiltinLintDiagnostics::UnknownCrateTypes(
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span,
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"did you mean".to_string(),
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format!("\"{}\"", candidate),
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),
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);
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} else {
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lint_buffer.buffer_lint(
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lint::builtin::UNKNOWN_CRATE_TYPES,
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ast::CRATE_NODE_ID,
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span,
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"invalid `crate_type` value",
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);
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}
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}
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}
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}
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}
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}
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const CRATE_TYPES: &[(Symbol, CrateType)] = &[
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(sym::rlib, CrateType::Rlib),
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(sym::dylib, CrateType::Dylib),
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(sym::cdylib, CrateType::Cdylib),
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(sym::lib, config::default_lib_output()),
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(sym::staticlib, CrateType::Staticlib),
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(sym::proc_dash_macro, CrateType::ProcMacro),
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(sym::bin, CrateType::Executable),
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];
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fn categorize_crate_type(s: Symbol) -> Option<CrateType> {
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Some(CRATE_TYPES.iter().find(|(key, _)| *key == s)?.1)
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}
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pub fn collect_crate_types(session: &Session, attrs: &[ast::Attribute]) -> Vec<CrateType> {
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// Unconditionally collect crate types from attributes to make them used
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let attr_types: Vec<CrateType> = attrs
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.iter()
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.filter_map(|a| {
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if session.check_name(a, sym::crate_type) {
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match a.value_str() {
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Some(s) => categorize_crate_type(s),
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_ => None,
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}
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} else {
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None
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}
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})
|
|
.collect();
|
|
|
|
// If we're generating a test executable, then ignore all other output
|
|
// styles at all other locations
|
|
if session.opts.test {
|
|
return vec![CrateType::Executable];
|
|
}
|
|
|
|
// Only check command line flags if present. If no types are specified by
|
|
// command line, then reuse the empty `base` Vec to hold the types that
|
|
// will be found in crate attributes.
|
|
let mut base = session.opts.crate_types.clone();
|
|
if base.is_empty() {
|
|
base.extend(attr_types);
|
|
if base.is_empty() {
|
|
base.push(output::default_output_for_target(session));
|
|
} else {
|
|
base.sort();
|
|
base.dedup();
|
|
}
|
|
}
|
|
|
|
base.retain(|crate_type| {
|
|
let res = !output::invalid_output_for_target(session, *crate_type);
|
|
|
|
if !res {
|
|
session.warn(&format!(
|
|
"dropping unsupported crate type `{}` for target `{}`",
|
|
*crate_type, session.opts.target_triple
|
|
));
|
|
}
|
|
|
|
res
|
|
});
|
|
|
|
base
|
|
}
|
|
|
|
pub fn build_output_filenames(
|
|
input: &Input,
|
|
odir: &Option<PathBuf>,
|
|
ofile: &Option<PathBuf>,
|
|
attrs: &[ast::Attribute],
|
|
sess: &Session,
|
|
) -> OutputFilenames {
|
|
match *ofile {
|
|
None => {
|
|
// "-" as input file will cause the parser to read from stdin so we
|
|
// have to make up a name
|
|
// We want to toss everything after the final '.'
|
|
let dirpath = (*odir).as_ref().cloned().unwrap_or_default();
|
|
|
|
// If a crate name is present, we use it as the link name
|
|
let stem = sess
|
|
.opts
|
|
.crate_name
|
|
.clone()
|
|
.or_else(|| rustc_attr::find_crate_name(&sess, attrs).map(|n| n.to_string()))
|
|
.unwrap_or_else(|| input.filestem().to_owned());
|
|
|
|
OutputFilenames::new(
|
|
dirpath,
|
|
stem,
|
|
None,
|
|
sess.opts.cg.extra_filename.clone(),
|
|
sess.opts.output_types.clone(),
|
|
)
|
|
}
|
|
|
|
Some(ref out_file) => {
|
|
let unnamed_output_types =
|
|
sess.opts.output_types.values().filter(|a| a.is_none()).count();
|
|
let ofile = if unnamed_output_types > 1 {
|
|
sess.warn(
|
|
"due to multiple output types requested, the explicitly specified \
|
|
output file name will be adapted for each output type",
|
|
);
|
|
None
|
|
} else {
|
|
if !sess.opts.cg.extra_filename.is_empty() {
|
|
sess.warn("ignoring -C extra-filename flag due to -o flag");
|
|
}
|
|
Some(out_file.clone())
|
|
};
|
|
if *odir != None {
|
|
sess.warn("ignoring --out-dir flag due to -o flag");
|
|
}
|
|
|
|
OutputFilenames::new(
|
|
out_file.parent().unwrap_or_else(|| Path::new("")).to_path_buf(),
|
|
out_file.file_stem().unwrap_or_default().to_str().unwrap().to_string(),
|
|
ofile,
|
|
sess.opts.cg.extra_filename.clone(),
|
|
sess.opts.output_types.clone(),
|
|
)
|
|
}
|
|
}
|
|
}
|
|
|
|
// Note: Also used by librustdoc, see PR #43348. Consider moving this struct elsewhere.
|
|
//
|
|
// FIXME: Currently the `everybody_loops` transformation is not applied to:
|
|
// * `const fn`, due to issue #43636 that `loop` is not supported for const evaluation. We are
|
|
// waiting for miri to fix that.
|
|
// * `impl Trait`, due to issue #43869 that functions returning impl Trait cannot be diverging.
|
|
// Solving this may require `!` to implement every trait, which relies on the an even more
|
|
// ambitious form of the closed RFC #1637. See also [#34511].
|
|
//
|
|
// [#34511]: https://github.com/rust-lang/rust/issues/34511#issuecomment-322340401
|
|
pub struct ReplaceBodyWithLoop<'a, 'b> {
|
|
within_static_or_const: bool,
|
|
nested_blocks: Option<Vec<ast::Block>>,
|
|
resolver: &'a mut Resolver<'b>,
|
|
}
|
|
|
|
impl<'a, 'b> ReplaceBodyWithLoop<'a, 'b> {
|
|
pub fn new(resolver: &'a mut Resolver<'b>) -> ReplaceBodyWithLoop<'a, 'b> {
|
|
ReplaceBodyWithLoop { within_static_or_const: false, nested_blocks: None, resolver }
|
|
}
|
|
|
|
fn run<R, F: FnOnce(&mut Self) -> R>(&mut self, is_const: bool, action: F) -> R {
|
|
let old_const = mem::replace(&mut self.within_static_or_const, is_const);
|
|
let old_blocks = self.nested_blocks.take();
|
|
let ret = action(self);
|
|
self.within_static_or_const = old_const;
|
|
self.nested_blocks = old_blocks;
|
|
ret
|
|
}
|
|
|
|
fn should_ignore_fn(ret_ty: &ast::FnRetTy) -> bool {
|
|
if let ast::FnRetTy::Ty(ref ty) = ret_ty {
|
|
fn involves_impl_trait(ty: &ast::Ty) -> bool {
|
|
match ty.kind {
|
|
ast::TyKind::ImplTrait(..) => true,
|
|
ast::TyKind::Slice(ref subty)
|
|
| ast::TyKind::Array(ref subty, _)
|
|
| ast::TyKind::Ptr(ast::MutTy { ty: ref subty, .. })
|
|
| ast::TyKind::Rptr(_, ast::MutTy { ty: ref subty, .. })
|
|
| ast::TyKind::Paren(ref subty) => involves_impl_trait(subty),
|
|
ast::TyKind::Tup(ref tys) => any_involves_impl_trait(tys.iter()),
|
|
ast::TyKind::Path(_, ref path) => {
|
|
path.segments.iter().any(|seg| match seg.args.as_deref() {
|
|
None => false,
|
|
Some(&ast::GenericArgs::AngleBracketed(ref data)) => {
|
|
data.args.iter().any(|arg| match arg {
|
|
ast::AngleBracketedArg::Arg(arg) => match arg {
|
|
ast::GenericArg::Type(ty) => involves_impl_trait(ty),
|
|
ast::GenericArg::Lifetime(_)
|
|
| ast::GenericArg::Const(_) => false,
|
|
},
|
|
ast::AngleBracketedArg::Constraint(c) => match c.kind {
|
|
ast::AssocTyConstraintKind::Bound { .. } => true,
|
|
ast::AssocTyConstraintKind::Equality { ref ty } => {
|
|
involves_impl_trait(ty)
|
|
}
|
|
},
|
|
})
|
|
}
|
|
Some(&ast::GenericArgs::Parenthesized(ref data)) => {
|
|
any_involves_impl_trait(data.inputs.iter())
|
|
|| ReplaceBodyWithLoop::should_ignore_fn(&data.output)
|
|
}
|
|
})
|
|
}
|
|
_ => false,
|
|
}
|
|
}
|
|
|
|
fn any_involves_impl_trait<'a, I: Iterator<Item = &'a P<ast::Ty>>>(mut it: I) -> bool {
|
|
it.any(|subty| involves_impl_trait(subty))
|
|
}
|
|
|
|
involves_impl_trait(ty)
|
|
} else {
|
|
false
|
|
}
|
|
}
|
|
|
|
fn is_sig_const(sig: &ast::FnSig) -> bool {
|
|
matches!(sig.header.constness, ast::Const::Yes(_))
|
|
|| ReplaceBodyWithLoop::should_ignore_fn(&sig.decl.output)
|
|
}
|
|
}
|
|
|
|
impl<'a> MutVisitor for ReplaceBodyWithLoop<'a, '_> {
|
|
fn visit_item_kind(&mut self, i: &mut ast::ItemKind) {
|
|
let is_const = match i {
|
|
ast::ItemKind::Static(..) | ast::ItemKind::Const(..) => true,
|
|
ast::ItemKind::Fn(_, ref sig, _, _) => Self::is_sig_const(sig),
|
|
_ => false,
|
|
};
|
|
self.run(is_const, |s| noop_visit_item_kind(i, s))
|
|
}
|
|
|
|
fn flat_map_trait_item(&mut self, i: P<ast::AssocItem>) -> SmallVec<[P<ast::AssocItem>; 1]> {
|
|
let is_const = match i.kind {
|
|
ast::AssocItemKind::Const(..) => true,
|
|
ast::AssocItemKind::Fn(_, ref sig, _, _) => Self::is_sig_const(sig),
|
|
_ => false,
|
|
};
|
|
self.run(is_const, |s| noop_flat_map_assoc_item(i, s))
|
|
}
|
|
|
|
fn flat_map_impl_item(&mut self, i: P<ast::AssocItem>) -> SmallVec<[P<ast::AssocItem>; 1]> {
|
|
self.flat_map_trait_item(i)
|
|
}
|
|
|
|
fn visit_anon_const(&mut self, c: &mut ast::AnonConst) {
|
|
self.run(true, |s| noop_visit_anon_const(c, s))
|
|
}
|
|
|
|
fn visit_block(&mut self, b: &mut P<ast::Block>) {
|
|
fn stmt_to_block(
|
|
rules: ast::BlockCheckMode,
|
|
s: Option<ast::Stmt>,
|
|
resolver: &mut Resolver<'_>,
|
|
) -> ast::Block {
|
|
ast::Block {
|
|
stmts: s.into_iter().collect(),
|
|
rules,
|
|
id: resolver.next_node_id(),
|
|
span: rustc_span::DUMMY_SP,
|
|
}
|
|
}
|
|
|
|
fn block_to_stmt(b: ast::Block, resolver: &mut Resolver<'_>) -> ast::Stmt {
|
|
let expr = P(ast::Expr {
|
|
id: resolver.next_node_id(),
|
|
kind: ast::ExprKind::Block(P(b), None),
|
|
span: rustc_span::DUMMY_SP,
|
|
attrs: AttrVec::new(),
|
|
tokens: None,
|
|
});
|
|
|
|
ast::Stmt {
|
|
id: resolver.next_node_id(),
|
|
kind: ast::StmtKind::Expr(expr),
|
|
span: rustc_span::DUMMY_SP,
|
|
}
|
|
}
|
|
|
|
let empty_block = stmt_to_block(BlockCheckMode::Default, None, self.resolver);
|
|
let loop_expr = P(ast::Expr {
|
|
kind: ast::ExprKind::Loop(P(empty_block), None),
|
|
id: self.resolver.next_node_id(),
|
|
span: rustc_span::DUMMY_SP,
|
|
attrs: AttrVec::new(),
|
|
tokens: None,
|
|
});
|
|
|
|
let loop_stmt = ast::Stmt {
|
|
id: self.resolver.next_node_id(),
|
|
span: rustc_span::DUMMY_SP,
|
|
kind: ast::StmtKind::Expr(loop_expr),
|
|
};
|
|
|
|
if self.within_static_or_const {
|
|
noop_visit_block(b, self)
|
|
} else {
|
|
visit_clobber(b.deref_mut(), |b| {
|
|
let mut stmts = vec![];
|
|
for s in b.stmts {
|
|
let old_blocks = self.nested_blocks.replace(vec![]);
|
|
|
|
stmts.extend(self.flat_map_stmt(s).into_iter().filter(|s| s.is_item()));
|
|
|
|
// we put a Some in there earlier with that replace(), so this is valid
|
|
let new_blocks = self.nested_blocks.take().unwrap();
|
|
self.nested_blocks = old_blocks;
|
|
stmts.extend(new_blocks.into_iter().map(|b| block_to_stmt(b, self.resolver)));
|
|
}
|
|
|
|
let mut new_block = ast::Block { stmts, ..b };
|
|
|
|
if let Some(old_blocks) = self.nested_blocks.as_mut() {
|
|
//push our fresh block onto the cache and yield an empty block with `loop {}`
|
|
if !new_block.stmts.is_empty() {
|
|
old_blocks.push(new_block);
|
|
}
|
|
|
|
stmt_to_block(b.rules, Some(loop_stmt), &mut self.resolver)
|
|
} else {
|
|
//push `loop {}` onto the end of our fresh block and yield that
|
|
new_block.stmts.push(loop_stmt);
|
|
|
|
new_block
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
// in general the pretty printer processes unexpanded code, so
|
|
// we override the default `visit_mac` method which panics.
|
|
fn visit_mac(&mut self, mac: &mut ast::MacCall) {
|
|
noop_visit_mac(mac, self)
|
|
}
|
|
}
|