Use OnceCell instead of Once

Author: ecstatic-morse

Cargo.lock

@@ -2327,6 +2327,9 @@ name = "once_cell"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d6a04cb71e910d0034815600180f62a95bf6e67942d7ab52a166a68c7d7e9cd0"
+dependencies = [
+ "parking_lot 0.9.0",
+]
 
 [[package]]
 name = "opaque-debug"

src/librustc_ast_lowering/lib.rs

@@ -269,7 +269,7 @@ pub fn lower_crate<'a, 'hir>(
     let _prof_timer = sess.prof.verbose_generic_activity("hir_lowering");
 
     LoweringContext {
-        crate_root: sess.parse_sess.injected_crate_name.try_get().copied(),
+        crate_root: sess.parse_sess.injected_crate_name.get().copied(),
         sess,
         resolver,
         nt_to_tokenstream,

src/librustc_codegen_llvm/context.rs

@@ -174,7 +174,7 @@ pub unsafe fn create_module(
         llvm::LLVMRustSetModulePICLevel(llmod);
         // PIE is potentially more effective than PIC, but can only be used in executables.
         // If all our outputs are executables, then we can relax PIC to PIE.
-        if sess.crate_types.get().iter().all(|ty| *ty == CrateType::Executable) {
+        if sess.crate_types().iter().all(|ty| *ty == CrateType::Executable) {
             llvm::LLVMRustSetModulePIELevel(llmod);
         }
     }

src/librustc_codegen_ssa/back/link.rs

@@ -53,7 +53,7 @@ pub fn link_binary<'a, B: ArchiveBuilder<'a>>(
 ) {
     let _timer = sess.timer("link_binary");
     let output_metadata = sess.opts.output_types.contains_key(&OutputType::Metadata);
-    for &crate_type in sess.crate_types.borrow().iter() {
+    for &crate_type in sess.crate_types().iter() {
         // Ignore executable crates if we have -Z no-codegen, as they will error.
         if (sess.opts.debugging_opts.no_codegen || !sess.opts.output_types.should_codegen())
             && !output_metadata
@@ -875,11 +875,8 @@ fn preserve_objects_for_their_debuginfo(sess: &Session) -> bool {
 
     // If we're only producing artifacts that are archives, no need to preserve
     // the objects as they're losslessly contained inside the archives.
-    let output_linked = sess
-        .crate_types
-        .borrow()
-        .iter()
-        .any(|&x| x != CrateType::Rlib && x != CrateType::Staticlib);
+    let output_linked =
+        sess.crate_types().iter().any(|&x| x != CrateType::Rlib && x != CrateType::Staticlib);
     if !output_linked {
         return false;
     }

src/librustc_codegen_ssa/back/linker.rs

@@ -44,8 +44,7 @@ impl LinkerInfo {
         LinkerInfo {
             exports: tcx
                 .sess
-                .crate_types
-                .borrow()
+                .crate_types()
                 .iter()
                 .map(|&c| (c, exported_symbols(tcx, c)))
                 .collect(),

src/librustc_codegen_ssa/back/symbol_export.rs

@@ -18,7 +18,7 @@ use rustc_middle::ty::{SymbolName, TyCtxt};
 use rustc_session::config::{CrateType, Sanitizer};
 
 pub fn threshold(tcx: TyCtxt<'_>) -> SymbolExportLevel {
-    crates_export_threshold(&tcx.sess.crate_types.borrow())
+    crates_export_threshold(&tcx.sess.crate_types())
 }
 
 fn crate_export_threshold(crate_type: CrateType) -> SymbolExportLevel {
@@ -212,7 +212,7 @@ fn exported_symbols_provider_local(
         }));
     }
 
-    if tcx.sess.crate_types.borrow().contains(&CrateType::Dylib) {
+    if tcx.sess.crate_types().contains(&CrateType::Dylib) {
         let symbol_name = metadata_symbol_name(tcx);
         let exported_symbol = ExportedSymbol::NoDefId(SymbolName::new(&symbol_name));
 

src/librustc_codegen_ssa/back/write.rs

@@ -382,7 +382,7 @@ pub struct CompiledModules {
 
 fn need_bitcode_in_object(sess: &Session) -> bool {
     let requested_for_rlib = sess.opts.cg.embed_bitcode
-        && sess.crate_types.borrow().contains(&CrateType::Rlib)
+        && sess.crate_types().contains(&CrateType::Rlib)
         && sess.opts.output_types.contains_key(&OutputType::Exe);
     let forced_by_target = sess.target.target.options.forces_embed_bitcode;
     requested_for_rlib || forced_by_target
@@ -991,7 +991,7 @@ fn start_executing_work<B: ExtraBackendMethods>(
     };
     let cgcx = CodegenContext::<B> {
         backend: backend.clone(),
-        crate_types: sess.crate_types.borrow().clone(),
+        crate_types: sess.crate_types().to_vec(),
         each_linked_rlib_for_lto,
         lto: sess.lto(),
         no_landing_pads: sess.panic_strategy() == PanicStrategy::Abort,
@@ -1812,7 +1812,7 @@ fn msvc_imps_needed(tcx: TyCtxt<'_>) -> bool {
     );
 
     tcx.sess.target.target.options.is_like_msvc &&
-        tcx.sess.crate_types.borrow().iter().any(|ct| *ct == CrateType::Rlib) &&
+        tcx.sess.crate_types().iter().any(|ct| *ct == CrateType::Rlib) &&
     // ThinLTO can't handle this workaround in all cases, so we don't
     // emit the `__imp_` symbols. Instead we make them unnecessary by disallowing
     // dynamic linking when linker plugin LTO is enabled.

src/librustc_codegen_ssa/base.rs

@@ -948,7 +948,7 @@ fn determine_cgu_reuse<'tcx>(tcx: TyCtxt<'tcx>, cgu: &CodegenUnit<'tcx>) -> CguR
         match compute_per_cgu_lto_type(
             &tcx.sess.lto(),
             &tcx.sess.opts,
-            &tcx.sess.crate_types.borrow(),
+            &tcx.sess.crate_types(),
             ModuleKind::Regular,
         ) {
             ComputedLtoType::No => CguReuse::PostLto,

src/librustc_driver/lib.rs

@@ -586,7 +586,7 @@ impl RustcDefaultCalls {
         if let Input::File(file) = compiler.input() {
             // FIXME: #![crate_type] and #![crate_name] support not implemented yet
             let attrs = vec![];
-            sess.crate_types.set(collect_crate_types(sess, &attrs));
+            sess.init_crate_types(collect_crate_types(sess, &attrs));
             let outputs = compiler.build_output_filenames(&sess, &attrs);
             let rlink_data = fs::read_to_string(file).unwrap_or_else(|err| {
                 sess.fatal(&format!("failed to read rlink file: {}", err));

src/librustc_driver/pretty.rs

@@ -396,7 +396,7 @@ pub fn print_after_parsing(
                 annotation.pp_ann(),
                 false,
                 parse.edition,
-                parse.injected_crate_name.try_get().is_some(),
+                parse.injected_crate_name.get().is_some(),
             )
         })
     } else {
@@ -438,7 +438,7 @@ pub fn print_after_hir_lowering<'tcx>(
                     annotation.pp_ann(),
                     true,
                     parse.edition,
-                    parse.injected_crate_name.try_get().is_some(),
+                    parse.injected_crate_name.get().is_some(),
                 )
             })
         }