Merge from rustc

Author: RalfJung

Cargo.lock

@@ -297,6 +297,7 @@ dependencies = [
  "sha2",
  "tar",
  "toml",
+ "xz2",
 ]
 
 [[package]]
@@ -1654,9 +1655,9 @@ dependencies = [
 
 [[package]]
 name = "icu_list"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "01a65ff0cab77c33c7e165c858eaa6e84a09f1e485dd495d9d0ae61083c6f786"
+checksum = "fd7ba7442d9235b689d4fdce17c452ea229934980fd81ba50cc28275752c9f90"
 dependencies = [
  "displaydoc",
  "icu_provider",
@@ -1666,9 +1667,9 @@ dependencies = [
 
 [[package]]
 name = "icu_locid"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "71d7a98ecb812760b5f077e55a4763edeefa7ccc30d6eb5680a70841ede81928"
+checksum = "3003f85dccfc0e238ff567693248c59153a46f4e6125ba4020b973cef4d1d335"
 dependencies = [
  "displaydoc",
  "litemap",
@@ -1679,9 +1680,9 @@ dependencies = [
 
 [[package]]
 name = "icu_provider"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a86816c97bc4e613086497f9479f63e120315e056763e8c4435604f98d21d82d"
+checksum = "8dc312a7b6148f7dfe098047ae2494d12d4034f48ade58d4f353000db376e305"
 dependencies = [
  "displaydoc",
  "icu_locid",
@@ -1695,9 +1696,9 @@ dependencies = [
 
 [[package]]
 name = "icu_provider_adapters"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e89bf33962b24bb48a4a21330c20c9ff17949338ea376360dd9eda2c209dca1"
+checksum = "f4ae1e2bd0c41728b77e7c46e9afdec5e2127d1eedacc684724667d50c126bd3"
 dependencies = [
  "icu_locid",
  "icu_provider",
@@ -1708,9 +1709,9 @@ dependencies = [
 
 [[package]]
 name = "icu_provider_macros"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9ddb07844c2ffc4c28840e799e9e54ff054393cf090740decf25624e9d94b93a"
+checksum = "dd8b728b9421e93eff1d9f8681101b78fa745e0748c95c655c83f337044a7e10"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2031,9 +2032,9 @@ checksum = "36eb31c1778188ae1e64398743890d0877fef36d11521ac60406b42016e8c2cf"
 
 [[package]]
 name = "litemap"
-version = "0.6.1"
+version = "0.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "575d8a551c59104b4df91269921e5eab561aa1b77c618dac0414b5d44a4617de"
+checksum = "3a04a5b2b6f54acba899926491d0a6c59d98012938ca2ab5befb281c034e8f94"
 
 [[package]]
 name = "lld-wrapper"
@@ -2060,9 +2061,9 @@ dependencies = [
 
 [[package]]
 name = "lzma-sys"
-version = "0.1.16"
+version = "0.1.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f24f76ec44a8ac23a31915d6e326bca17ce88da03096f1ff194925dc714dac99"
+checksum = "5fda04ab3764e6cde78b9974eec4f779acaba7c4e84b36eca3cf77c581b85d27"
 dependencies = [
  "cc",
  "libc",
@@ -2908,9 +2909,9 @@ dependencies = [
 
 [[package]]
 name = "rustc-build-sysroot"
-version = "0.4.1"
+version = "0.4.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d65b1271cdac365b71b59570ea35d945dea2dd2cc47eba3d33b4bd1e0190ac6d"
+checksum = "8ed2a90dfa5232ed5ff21d53d4df655f315ab316ea06fc508f1c74bcedb1ce6c"
 dependencies = [
  "anyhow",
  "rustc_version",
@@ -3164,6 +3165,7 @@ dependencies = [
  "rustc_expand",
  "rustc_feature",
  "rustc_fluent_macro",
+ "rustc_index",
  "rustc_lexer",
  "rustc_lint_defs",
  "rustc_macros",
@@ -4059,6 +4061,7 @@ dependencies = [
  "indexmap",
  "rustc_macros",
  "smallvec",
+ "tempfile",
  "thin-vec",
 ]
 
@@ -4737,6 +4740,15 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "sysroot"
+version = "0.0.0"
+dependencies = [
+ "proc_macro",
+ "std",
+ "test",
+]
+
 [[package]]
 name = "tar"
 version = "0.4.38"
@@ -4821,7 +4833,6 @@ dependencies = [
  "getopts",
  "panic_abort",
  "panic_unwind",
- "proc_macro",
  "std",
 ]
 
@@ -5659,9 +5670,9 @@ dependencies = [
 
 [[package]]
 name = "xz2"
-version = "0.1.6"
+version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c179869f34fc7c01830d3ce7ea2086bc3a07e0d35289b667d0a8bf910258926c"
+checksum = "388c44dc09d76f1536602ead6d325eb532f5c122f17782bd57fb47baeeb767e2"
 dependencies = [
  "lzma-sys",
 ]
@@ -5697,9 +5708,9 @@ dependencies = [
 
 [[package]]
 name = "yoke"
-version = "0.7.0"
+version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "222180af14a6b54ef2c33493c1eff77ae95a3687a21b243e752624006fb8f26e"
+checksum = "1848075a23a28f9773498ee9a0f2cf58fcbad4f8c0ccf84a210ab33c6ae495de"
 dependencies = [
  "serde",
  "stable_deref_trait",
@@ -5742,9 +5753,9 @@ dependencies = [
 
 [[package]]
 name = "zerovec"
-version = "0.9.2"
+version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "154df60c74c4a844bc04a53cef4fc18a909d3ea07e19f5225eaba86209da3aa6"
+checksum = "198f54134cd865f437820aa3b43d0ad518af4e68ee161b444cdd15d8e567c8ea"
 dependencies = [
  "yoke",
  "zerofrom",

Cargo.toml

@@ -2,7 +2,7 @@
 members = [
   "compiler/rustc",
   "library/std",
-  "library/test",
+  "library/sysroot",
   "src/rustdoc-json-types",
   "src/tools/build_helper",
   "src/tools/cargotest",

compiler/rustc_ast/src/ast.rs

@@ -287,12 +287,20 @@ pub enum TraitBoundModifier {
     /// No modifiers
     None,
 
+    /// `!Trait`
+    Negative,
+
     /// `?Trait`
     Maybe,
 
     /// `~const Trait`
     MaybeConst,
 
+    /// `~const !Trait`
+    //
+    // This parses but will be rejected during AST validation.
+    MaybeConstNegative,
+
     /// `~const ?Trait`
     //
     // This parses but will be rejected during AST validation.
@@ -2446,6 +2454,16 @@ impl fmt::Debug for ImplPolarity {
     }
 }
 
+#[derive(Copy, Clone, PartialEq, Encodable, Decodable, HashStable_Generic)]
+pub enum BoundPolarity {
+    /// `Type: Trait`
+    Positive,
+    /// `Type: !Trait`
+    Negative(Span),
+    /// `Type: ?Trait`
+    Maybe(Span),
+}
+
 #[derive(Clone, Encodable, Decodable, Debug)]
 pub enum FnRetTy {
     /// Returns type is not specified.

compiler/rustc_ast_lowering/src/lib.rs

@@ -1368,13 +1368,17 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
                         this.arena.alloc_from_iter(bounds.iter().filter_map(|bound| match bound {
                             GenericBound::Trait(
                                 ty,
-                                TraitBoundModifier::None | TraitBoundModifier::MaybeConst,
+                                TraitBoundModifier::None
+                                | TraitBoundModifier::MaybeConst
+                                | TraitBoundModifier::Negative,
                             ) => Some(this.lower_poly_trait_ref(ty, itctx)),
                             // `~const ?Bound` will cause an error during AST validation
                             // anyways, so treat it like `?Bound` as compilation proceeds.
                             GenericBound::Trait(
                                 _,
-                                TraitBoundModifier::Maybe | TraitBoundModifier::MaybeConstMaybe,
+                                TraitBoundModifier::Maybe
+                                | TraitBoundModifier::MaybeConstMaybe
+                                | TraitBoundModifier::MaybeConstNegative,
                             ) => None,
                             GenericBound::Outlives(lifetime) => {
                                 if lifetime_bound.is_none() {
@@ -2421,11 +2425,20 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             TraitBoundModifier::None => hir::TraitBoundModifier::None,
             TraitBoundModifier::MaybeConst => hir::TraitBoundModifier::MaybeConst,
 
+            TraitBoundModifier::Negative => {
+                if self.tcx.features().negative_bounds {
+                    hir::TraitBoundModifier::Negative
+                } else {
+                    hir::TraitBoundModifier::None
+                }
+            }
+
             // `MaybeConstMaybe` will cause an error during AST validation, but we need to pick a
             // placeholder for compilation to proceed.
             TraitBoundModifier::MaybeConstMaybe | TraitBoundModifier::Maybe => {
                 hir::TraitBoundModifier::Maybe
             }
+            TraitBoundModifier::MaybeConstNegative => hir::TraitBoundModifier::MaybeConst,
         }
     }
 

compiler/rustc_ast_passes/messages.ftl

@@ -206,7 +206,7 @@ ast_passes_tilde_const_disallowed = `~const` is not allowed here
     .closure = closures cannot have `~const` trait bounds
     .function = this function is not `const`, so it cannot have `~const` trait bounds
 
-ast_passes_optional_const_exclusive = `~const` and `?` are mutually exclusive
+ast_passes_optional_const_exclusive = `~const` and `{$modifier}` are mutually exclusive
 
 ast_passes_const_and_async = functions cannot be both `const` and `async`
     .const = `const` because of this
@@ -235,3 +235,9 @@ ast_passes_incompatible_features = `{$f1}` and `{$f2}` are incompatible, using t
     .help = remove one of these features
 
 ast_passes_show_span = {$msg}
+
+ast_passes_negative_bound_not_supported =
+    negative bounds are not supported
+
+ast_passes_constraint_on_negative_bound =
+    associated type constraints not allowed on negative bounds

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -1168,12 +1168,27 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                     });
                 }
                 (_, TraitBoundModifier::MaybeConstMaybe) => {
-                    self.err_handler().emit_err(errors::OptionalConstExclusive {span: bound.span()});
+                    self.err_handler().emit_err(errors::OptionalConstExclusive {span: bound.span(), modifier: "?" });
+                }
+                (_, TraitBoundModifier::MaybeConstNegative) => {
+                    self.err_handler().emit_err(errors::OptionalConstExclusive {span: bound.span(), modifier: "!" });
                 }
                 _ => {}
             }
         }
 
+        // Negative trait bounds are not allowed to have associated constraints
+        if let GenericBound::Trait(trait_ref, TraitBoundModifier::Negative) = bound
+            && let Some(segment) = trait_ref.trait_ref.path.segments.last()
+            && let Some(ast::GenericArgs::AngleBracketed(args)) = segment.args.as_deref()
+        {
+            for arg in &args.args {
+                if let ast::AngleBracketedArg::Constraint(constraint) = arg {
+                    self.err_handler().emit_err(errors::ConstraintOnNegativeBound { span: constraint.span });
+                }
+            }
+        }
+
         visit::walk_param_bound(self, bound)
     }
 

compiler/rustc_ast_passes/src/errors.rs

@@ -567,6 +567,7 @@ pub enum TildeConstReason {
 pub struct OptionalConstExclusive {
     #[primary_span]
     pub span: Span,
+    pub modifier: &'static str,
 }
 
 #[derive(Diagnostic)]
@@ -693,3 +694,17 @@ pub struct ShowSpan {
     pub span: Span,
     pub msg: &'static str,
 }
+
+#[derive(Diagnostic)]
+#[diag(ast_passes_negative_bound_not_supported)]
+pub struct NegativeBoundUnsupported {
+    #[primary_span]
+    pub span: Span,
+}
+
+#[derive(Diagnostic)]
+#[diag(ast_passes_constraint_on_negative_bound)]
+pub struct ConstraintOnNegativeBound {
+    #[primary_span]
+    pub span: Span,
+}

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -603,6 +603,12 @@ pub fn check_crate(krate: &ast::Crate, sess: &Session) {
     gate_all!(dyn_star, "`dyn*` trait objects are experimental");
     gate_all!(const_closures, "const closures are experimental");
 
+    if !visitor.features.negative_bounds {
+        for &span in spans.get(&sym::negative_bounds).iter().copied().flatten() {
+            sess.emit_err(errors::NegativeBoundUnsupported { span });
+        }
+    }
+
     // All uses of `gate_all!` below this point were added in #65742,
     // and subsequently disabled (with the non-early gating readded).
     // We emit an early future-incompatible warning for these.

compiler/rustc_ast_pretty/src/pprust/state.rs

@@ -1570,12 +1570,19 @@ impl<'a> State<'a> {
                 GenericBound::Trait(tref, modifier) => {
                     match modifier {
                         TraitBoundModifier::None => {}
+                        TraitBoundModifier::Negative => {
+                            self.word("!");
+                        }
                         TraitBoundModifier::Maybe => {
                             self.word("?");
                         }
                         TraitBoundModifier::MaybeConst => {
                             self.word_space("~const");
                         }
+                        TraitBoundModifier::MaybeConstNegative => {
+                            self.word_space("~const");
+                            self.word("!");
+                        }
                         TraitBoundModifier::MaybeConstMaybe => {
                             self.word_space("~const");
                             self.word("?");

compiler/rustc_baked_icu_data/Cargo.toml

@@ -4,11 +4,11 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
-icu_list = "1.1.0"
-icu_locid = "1.1.0"
-icu_provider = "1.1.0"
-icu_provider_adapters = "1.1.0"
-zerovec = "0.9.2"
+icu_list = "1.2"
+icu_locid = "1.2"
+icu_provider = "1.2"
+icu_provider_adapters = "1.2"
+zerovec = "0.9.4"
 
 [features]
 rustc_use_parallel_compiler = ['icu_provider/sync']