Merge branch 'main' of github.com:apple/swift into maxd/main-merge

# Conflicts:
#	test/Concurrency/Runtime/checked_continuation.swift

Author: MaxDesiatov

CMakeLists.txt

@@ -530,6 +530,18 @@ if(SWIFT_ENABLE_DISPATCH AND NOT CMAKE_SYSTEM_NAME STREQUAL Darwin)
   endif()
 endif()
 
+set(SWIFT_STDLIB_AVAILABILITY_DEFINITIONS
+  "SwiftStdlib 5.0:macOS 10.14.4, iOS 12.2, watchOS 5.2, tvOS 12.2"
+  "SwiftStdlib 5.1:macOS 10.15, iOS 13.0, watchOS 6.0, tvOS 13.0"
+  "SwiftStdlib 5.2:macOS 10.15.4, iOS 13.4, watchOS 6.2, tvOS 13.4"
+  "SwiftStdlib 5.3:macOS 11.0, iOS 14.0, watchOS 7.0, tvOS 14.0"
+  "SwiftStdlib 5.4:macOS 11.3, iOS 14.5, watchOS 7.4, tvOS 14.5"
+  "SwiftStdlib 5.5:macOS 12.0, iOS 15.0, watchOS 8.0, tvOS 15.0"
+  "SwiftStdlib 5.6:macOS 9999, iOS 9999, watchOS 9999, tvOS 9999"
+  "SwiftStdlib 9999:macOS 9999, iOS 9999, watchOS 9999, tvOS 9999" # Unknown future release
+  CACHE STRING
+  "Availability macros for stdlib versions")
+
 #
 # Include CMake modules
 #

cmake/caches/Runtime-Windows-aarch64.cmake

@@ -0,0 +1,21 @@
+
+set(SWIFT_HOST_VARIANT_SDK WINDOWS CACHE STRING "")
+set(SWIFT_HOST_VARIANT_ARCH aarch64 CACHE STRING "")
+
+# NOTE(compnerd) disable the tools, we are trying to build just the standard
+# library.
+set(SWIFT_INCLUDE_TOOLS NO CACHE BOOL "")
+
+# NOTE(compnerd) cannot build tests since the tests require the toolchain
+set(SWIFT_INCLUDE_TESTS NO CACHE BOOL "")
+
+# NOTE(compnerd) cannot build docs since that requires perl
+set(SWIFT_INCLUDE_DOCS NO CACHE BOOL "")
+
+# NOTE(compnerd) these are part of the toolchain, not the runtime.
+set(SWIFT_BUILD_SYNTAXPARSERLIB NO CACHE BOOL "")
+set(SWIFT_BUILD_SOURCEKIT NO CACHE BOOL "")
+
+# NOTE(compnerd) build with the compiler specified, not a just built compiler.
+set(SWIFT_BUILD_RUNTIME_WITH_HOST_COMPILER YES CACHE BOOL "")
+

docs/StandardLibraryProgrammersManual.md

@@ -298,34 +298,63 @@ Just like access control modifiers, we prefer to put `@available` attributes on
 
 ```swift
 // 😢👎
-@available(macOS 10.6, iOS 10, watchOS 3, tvOS 12, *)
+@available(SwiftStdlib 5.2, *)
 extension String {
   public func blanch() { ... }
   public func roast() { ... }
 }
 
 // 🥲👍
 extension String {
-  @available(macOS 10.6, iOS 10, watchOS 3, tvOS 12, *)
+  @available(SwiftStdlib 5.2, *)
   public func blanch() { ... }
 
-  @available(macOS 10.6, iOS 10, watchOS 3, tvOS 12, *)
+  @available(SwiftStdlib 5.2, *)
   public func roast() { ... }
 }
 ```
 
 This coding style is enforced by the ABI checker -- it will complain if an extension member declaration that needs an availability doesn't have it directly attached.
 
-Features under development that haven't been released yet must be marked with the placeholder version number `9999`. This special version is always considered available in custom builds of the Swift toolchain (including development snapshots), but not in any ABI-stable production release.
+This repository defines a set of availability macros (of the form `SwiftStdlib x.y`) that map Swift Stdlib releases to the OS versions that shipped them, for all ABI stable platforms. The following two definitions are equivalent, but the second one is less error-prone, so we prefer that:
 
 ```swift
+extension String {
+  // 😵‍💫👎
+  @available(macOS 10.15.4, iOS 13.4, watchOS 6.2, tvOS 13.4, *)
+  public func fiddle() { ... }
+
+  // 😎👍
+  @available(SwiftStdlib 5.2, *)
+  public func fiddle() { ... }
+}
+```
+
+(Mistakes in the OS version number list are very easy to miss during review, but can have major ABI consequences.)
+
+This is especially important for newly introduced APIs, where the corresponding OS releases may not even be known yet. 
+
+Features under development that haven't shipped yet must be marked as available in the placeholder OS version `9999`. This special version is always considered available in custom builds of the Swift toolchain (including development snapshots), but not in any ABI-stable production release. 
+
+Never explicitly spell out such placeholder availability -- instead, use the `SwiftStdlib` macro corresponding to the Swift version we're currently working on:
+
+```swift
+// 😵‍💫👎
 @available(macOS 9999, iOS 9999, watchOS 9999, tvOS 9999, *)
 public struct FutureFeature {
   ...
 }
+
+// 😎👍
+@available(SwiftStdlib 6.3, *) // Or whatever
+public struct FutureFeature {
+  ...
+}
 ```
 
-On these platforms, the Swift Standard Library ships as an integrated part of the operating system; as such, it is the platform owners' responsibility to update these placeholder version numbers to actual versions as part of their release process.
+This way, platform owners can easily update declarations to the correct set of version numbers by simply changing the definition of the macro, rather than having to update each individual declaration.
+
+If we haven't defined a version number for the "next" Swift release yet, please use the special placeholder version `SwiftStdlib 9999`, which always expands to 9999 versions. Declarations that use this version will need to be manually updated once we decide on the corresponding Swift version number.
 
 ## Internals
 

include/swift/AST/ASTContext.h

@@ -350,8 +350,14 @@ class ASTContext final {
   /// Cache of module names that fail the 'canImport' test in this context.
   mutable llvm::SmallPtrSet<Identifier, 8> FailedModuleImportNames;
 
-  /// Mapping between aliases and real (physical) names of imported or referenced modules.
-  mutable llvm::DenseMap<Identifier, Identifier> ModuleAliasMap;
+  /// Set if a `-module-alias` was passed. Used to store mapping between module aliases and
+  /// their corresponding real names, and vice versa for a reverse lookup, which is needed to check
+  /// if the module names appearing in source files are aliases or real names.
+  /// \see ASTContext::getRealModuleName.
+  ///
+  /// The boolean in the value indicates whether or not the entry is keyed by an alias vs real name,
+  /// i.e. true if the entry is [key: alias_name, value: (real_name, true)].
+  mutable llvm::DenseMap<Identifier, std::pair<Identifier, bool>> ModuleAliasMap;
 
   /// Retrieve the allocator for the given arena.
   llvm::BumpPtrAllocator &
@@ -483,9 +489,23 @@ class ASTContext final {
   /// are the real (physical) module names on disk.
   void setModuleAliases(const llvm::StringMap<StringRef> &aliasMap);
 
-  /// Retrieve the actual module name if a module alias is used via '-module-alias Foo=X', where Foo is
-  /// a module alias and X is the real (physical) name. Returns \p key if no aliasing is used.
-  Identifier getRealModuleName(Identifier key) const;
+  /// Look up the module alias map by the given \p key.
+  ///
+  /// \param key A module alias or real name to look up the map by
+  /// \param alwaysReturnRealName Indicates whether it should always retrieve the real module name
+  ///        given \p key. Defaults to true. This takes a higher precedence than
+  ///        \p lookupAliasFromReal.
+  /// \param lookupAliasFromReal Indicates whether to look up an alias by treating \p key
+  ///        as a real name. Defaults to false.
+  /// \return The real name or alias mapped to the key.
+  ///         If \p alwaysReturnRealName is true, return the real module name if \p key is an alias
+  ///         or the key itself since that's the real name.
+  ///         If \p lookupAliasFromReal is true, and \p alwaysReturnRealName is false, return
+  ///         only if \p key is a real name, else an empty Identifier.
+  ///         If no aliasing is used, return \p key.
+  Identifier getRealModuleName(Identifier key,
+                               bool alwaysReturnRealName = true,
+                               bool lookupAliasFromReal = false) const;
 
   /// Decide how to interpret two precedence groups.
   Associativity associateInfixOperators(PrecedenceGroupDecl *left,

include/swift/AST/Attr.def

@@ -676,7 +676,7 @@ SIMPLE_DECL_ATTR(_noImplicitCopy, NoImplicitCopy,
   UserInaccessible |
   ABIStableToAdd | ABIBreakingToRemove |
   APIStableToAdd | APIBreakingToRemove |
-  OnVar,
+  OnParam | OnVar,
   122)
 
 SIMPLE_DECL_ATTR(_noLocks, NoLocks,

include/swift/AST/Decl.h

@@ -4168,6 +4168,7 @@ class ProtocolDecl final : public NominalTypeDecl {
   friend class StructuralRequirementsRequest;
   friend class ProtocolDependenciesRequest;
   friend class RequirementSignatureRequest;
+  friend class RequirementSignatureRequestRQM;
   friend class ProtocolRequiresClassRequest;
   friend class ExistentialConformsToSelfRequest;
   friend class InheritedProtocolsRequest;
@@ -5371,6 +5372,10 @@ class ParamDecl : public VarDecl {
     Bits.ParamDecl.defaultArgumentKind = static_cast<unsigned>(K);
   }
 
+  bool isNoImplicitCopy() const {
+    return getAttrs().hasAttribute<NoImplicitCopyAttr>();
+  }
+
   /// Whether this parameter has a default argument expression available.
   ///
   /// Note that this will return false for deserialized declarations, which only

include/swift/AST/DiagnosticsParse.def

@@ -302,6 +302,9 @@ ERROR(getset_cannot_be_implied,none,
 // Import
 ERROR(decl_expected_module_name,none,
       "expected module name in import declaration", ())
+ERROR(expected_module_alias,none,
+      "cannot refer to module as %0 because it has been aliased; use %1 "
+      "instead", (Identifier, Identifier))
 
 // Extension
 ERROR(expected_lbrace_extension,PointsToFirstBadToken,

include/swift/AST/DiagnosticsSema.def

@@ -2912,7 +2912,7 @@ WARNING(warn_implementation_only_conflict,none,
         (Identifier))
 NOTE(implementation_only_conflict_here,none,
      "imported as implementation-only here", ())
-WARNING(warn_public_import_of_private_module,none,
+ERROR(error_public_import_of_private_module,none,
         "private module %0 is imported publicly from the public module %1",
         (Identifier, Identifier))
 
@@ -4351,6 +4351,10 @@ NOTE(note_add_async_to_function,none,
 NOTE(note_add_nonisolated_to_decl,none,
      "add 'nonisolated' to %0 to make this %1 not isolated to the actor",
      (DeclName, DescriptiveDeclKind))
+NOTE(note_add_async_and_throws_to_decl,none,
+     "mark the protocol requirement %0 '%select{|async|throws|async throws}1' "
+     "in order witness it with 'distributed' function declared in distributed actor %2",
+     (DeclName, unsigned, DeclName))
 NOTE(note_add_distributed_to_decl,none,
      "add 'distributed' to %0 to make this %1 witness the protocol requirement",
      (DeclName, DescriptiveDeclKind))
@@ -4484,11 +4488,11 @@ NOTE(actor_isolated_sync_func,none,
      "calls to %0 %1 from outside of its actor context are "
      "implicitly asynchronous",
      (DescriptiveDeclKind, DeclName))
-NOTE(distributed_actor_isolated_method_note,none,
-     "only 'distributed' functions can be called from outside the distributed actor", // TODO(distributed): improve error message
-     ())
+NOTE(note_distributed_actor_isolated_method,none,
+     "distributed actor-isolated %0 %1 declared here",
+     (DescriptiveDeclKind, DeclName))
 ERROR(distributed_actor_isolated_method,none,
-      "only 'distributed' functions can be called from outside the distributed actor", // TODO(distributed): improve error message to be more like 'non-distributed' ... defined here
+      "only 'distributed' functions can be called on a potentially remote distributed actor",
       ())
 ERROR(distributed_actor_func_param_not_codable,none,
       "distributed function parameter '%0' of type %1 does not conform to 'Codable'",
@@ -4497,7 +4501,7 @@ ERROR(distributed_actor_func_result_not_codable,none,
       "distributed function result type %0 does not conform to 'Codable'",
       (Type))
 ERROR(distributed_actor_remote_func_implemented_manually,none,
-      "Distributed function's %0 remote counterpart %1 cannot not be implemented manually.",
+      "distributed function's %0 remote counterpart %1 cannot not be implemented manually.",
       (Identifier, Identifier))
 ERROR(nonisolated_distributed_actor_storage,none,
       "'nonisolated' can not be applied to distributed actor stored properties",
@@ -4523,6 +4527,9 @@ WARNING(shared_mutable_state_access,none,
 ERROR(actor_isolated_witness,none,
      "actor-isolated %0 %1 cannot be used to satisfy a protocol requirement",
      (DescriptiveDeclKind, DeclName))
+ERROR(distributed_actor_isolated_witness,none,
+     "distributed actor-isolated %0 %1 cannot be used to satisfy a protocol requirement",
+     (DescriptiveDeclKind, DeclName))
 ERROR(global_actor_isolated_requirement,none,
       "%0 %1 must be isolated to the global actor %2 to satisfy corresponding "
       "requirement from protocol %3",
@@ -6040,8 +6047,8 @@ ERROR(experimental_moveonly_feature_can_only_be_used_when_enabled,
       none, "Can not use feature when experimental move only is disabled! Pass"
       " the frontend flag -enable-experimental-move-only to swift to enable "
       "the usage of this language feature", ())
-ERROR(noimplicitcopy_attr_valid_only_on_local_let,
-      none, "'@_noImplicitCopy' attribute can only be applied to local lets", ())
+ERROR(noimplicitcopy_attr_valid_only_on_local_let_params,
+      none, "'@_noImplicitCopy' attribute can only be applied to local lets and params", ())
 ERROR(noimplicitcopy_attr_invalid_in_generic_context,
       none, "'@_noImplicitCopy' attribute cannot be applied to entities in generic contexts", ())
 

include/swift/AST/IRGenOptions.h

@@ -311,6 +311,7 @@ class IRGenOptions {
   /// Used on Windows to avoid cross-module references.
   unsigned LazyInitializeClassMetadata : 1;
   unsigned LazyInitializeProtocolConformances : 1;
+  unsigned IndirectAsyncFunctionPointer : 1;
 
   /// Normally if the -read-legacy-type-info flag is not specified, we look for
   /// a file named "legacy-<arch>.yaml" in SearchPathOpts.RuntimeLibraryPath.
@@ -417,7 +418,8 @@ class IRGenOptions {
         ValueNames(false), EnableReflectionMetadata(true),
         EnableReflectionNames(true), EnableAnonymousContextMangledNames(false),
         ForcePublicLinkage(false), LazyInitializeClassMetadata(false),
-        LazyInitializeProtocolConformances(false), DisableLegacyTypeInfo(false),
+        LazyInitializeProtocolConformances(false),
+        IndirectAsyncFunctionPointer(false), DisableLegacyTypeInfo(false),
         PrespecializeGenericMetadata(false), UseIncrementalLLVMCodeGen(true),
         UseTypeLayoutValueHandling(true), ForceStructTypeLayouts(false),
         GenerateProfile(false), EnableDynamicReplacementChaining(false),

include/swift/AST/KnownSDKTypes.def

@@ -45,7 +45,6 @@ KNOWN_SDK_TYPE_DECL(Concurrency, TaskLocal, ClassDecl, 1)
 
 // Distributed actors
 KNOWN_SDK_TYPE_DECL(Distributed, DistributedActor, ProtocolDecl, 0)
-KNOWN_SDK_TYPE_DECL(Distributed, ActorTransport, ProtocolDecl, 0)
 KNOWN_SDK_TYPE_DECL(Distributed, ActorIdentity, ProtocolDecl, 0)
 KNOWN_SDK_TYPE_DECL(Distributed, AnyActorIdentity, StructDecl, 0)