library: Move CStr to libcore, and CString to liballoc

Cargo.lock

@@ -731,9 +731,9 @@ dependencies = [
 
 [[package]]
 name = "compiler_builtins"
-version = "0.1.70"
+version = "0.1.71"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "80873f979f0a344a4ade87c2f70d9ccf5720b83b10c97ec7cd745895d021e85a"
+checksum = "163437f05ca8f29d7e9128ea728dedf5eb620e445fbca273641d3a3050305f23"
 dependencies = [
  "cc",
  "rustc-std-workspace-core",

compiler/rustc_hir/src/lang_items.rs

@@ -326,6 +326,8 @@ language_item_table! {
  Range, sym::Range, range_struct, Target::Struct, GenericRequirement::None;
  RangeToInclusive, sym::RangeToInclusive, range_to_inclusive_struct, Target::Struct, GenericRequirement::None;
  RangeTo, sym::RangeTo, range_to_struct, Target::Struct, GenericRequirement::None;
+
+ CStr, sym::CStr, c_str, Target::Struct, GenericRequirement::None;
 }
 
 pub enum GenericRequirement {

compiler/rustc_metadata/src/creader.rs

@@ -417,6 +417,7 @@ impl<'a> CrateLoader<'a> {
 
  let crate_metadata = CrateMetadata::new(
  self.sess,
+ &self.cstore,
  metadata,
  crate_root,
  raw_proc_macros,

compiler/rustc_metadata/src/rmeta/decoder.rs

@@ -1,6 +1,6 @@
 // Decoding metadata from a single crate's metadata
 
-use crate::creader::CrateMetadataRef;
+use crate::creader::{CStore, CrateMetadataRef};
 use crate::rmeta::table::{FixedSizeEncoding, Table};
 use crate::rmeta::*;
 
@@ -1737,6 +1737,7 @@ impl<'a, 'tcx> CrateMetadataRef<'a> {
 impl CrateMetadata {
  crate fn new(
  sess: &Session,
+ cstore: &CStore,
  blob: MetadataBlob,
  root: CrateRoot<'static>,
  raw_proc_macros: Option<&'static [ProcMacro]>,
@@ -1752,11 +1753,6 @@ impl CrateMetadata {
  .decode((&blob, sess))
  .map(|trait_impls| (trait_impls.trait_id, trait_impls.impls))
  .collect();
- let incoherent_impls = root
- .incoherent_impls
- .decode((&blob, sess))
- .map(|incoherent_impls| (incoherent_impls.self_ty, incoherent_impls.impls))
- .collect();
  let alloc_decoding_state =
  AllocDecodingState::new(root.interpret_alloc_index.decode(&blob).collect());
  let dependencies = Lock::new(cnum_map.iter().cloned().collect());
@@ -1765,11 +1761,11 @@ impl CrateMetadata {
  // that does not copy any data. It just does some data verification.
  let def_path_hash_map = root.def_path_hash_map.decode(&blob);
 
- CrateMetadata {
+ let mut cdata = CrateMetadata {
  blob,
  root,
  trait_impls,
- incoherent_impls,
+ incoherent_impls: Default::default(),
  raw_proc_macros,
  source_map_import_info: OnceCell::new(),
  def_path_hash_map,
@@ -1786,7 +1782,17 @@ impl CrateMetadata {
  hygiene_context: Default::default(),
  def_key_cache: Default::default(),
  def_path_hash_cache: Default::default(),
- }
+ };
+
+ // Need `CrateMetadataRef` to decode `DefId`s in simplified types.
+ cdata.incoherent_impls = cdata
+ .root
+ .incoherent_impls
+ .decode(CrateMetadataRef { cdata: &cdata, cstore })
+ .map(|incoherent_impls| (incoherent_impls.self_ty, incoherent_impls.impls))
+ .collect();
+
+ cdata
  }
 
  crate fn dependencies(&self) -> LockGuard<'_, Vec<CrateNum>> {

compiler/rustc_typeck/src/check/method/probe.rs

@@ -644,7 +644,11 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
  self.assemble_inherent_impl_candidates_for_type(p.def_id());
  }
  ty::Adt(def, _) => {
- self.assemble_inherent_impl_candidates_for_type(def.did());
+ let def_id = def.did();
+ self.assemble_inherent_impl_candidates_for_type(def_id);
+ if Some(def_id) == self.tcx.lang_items().c_str() {
+ self.assemble_inherent_candidates_for_incoherent_ty(raw_self_ty);
+ }
  }
  ty::Foreign(did) => {
  self.assemble_inherent_impl_candidates_for_type(did);

compiler/rustc_typeck/src/coherence/inherent_impls.rs

@@ -55,7 +55,12 @@ impl<'tcx> ItemLikeVisitor<'_> for InherentCollect<'tcx> {
  let self_ty = self.tcx.type_of(item.def_id);
  match *self_ty.kind() {
  ty::Adt(def, _) => {
- self.check_def_id(item, def.did());
+ let def_id = def.did();
+ if !def_id.is_local() && Some(def_id) == self.tcx.lang_items().c_str() {
+ self.check_primitive_impl(item.def_id, self_ty, items, ty.span)
+ } else {
+ self.check_def_id(item, def_id);
+ }
  }
  ty::Foreign(did) => {
  self.check_def_id(item, did);