Merge branch 'main'

Author: salinas-miguel

CHANGELOG.md

@@ -5,6 +5,54 @@ _**Note:** This is in reverse chronological order, so newer entries are added to
 
 Swift 5.6
 ---------
+
+* References to `Self` or so-called "`Self` requirements" in the type signatures
+  of protocol members are now correctly detected in the parent of a nested type.
+  As a result, protocol members that fall under this overlooked case are no longer
+  available on values of protocol type:
+
+  ```swift
+  struct Outer<T> {
+    struct Inner {}
+  }
+
+  protocol P {}
+  extension P {
+    func method(arg: Outer<Self>.Inner) {}
+  }
+
+  func test(p: P) {
+    // error: 'method' has a 'Self' requirement and cannot be used on a value of
+    // protocol type (use a generic constraint instead).
+    _ = p.method
+  }
+  ``` 
+
+* [SE-0324][]:
+
+  Relax diagnostics for pointer arguments to C functions. The Swift
+  compiler now accepts limited pointer type mismatches when directly
+  calling functions imported from C as long as the C language allows
+  those pointer types to alias. Consequently, any Swift
+  `Unsafe[Mutable]Pointer<T>` or `Unsafe[Mutable]RawPointer` may be
+  passed to C function arguments declared as `[signed|unsigned] char
+  *`. Swift `Unsafe[Mutable]Pointer<T>` can also be passed to C
+  function arguments with an integer type that differs from `T` only
+  in its signedness.
+
+  For example, after importing a C function declaration:
+  ```c
+  long long decode_int64(const char *ptr_to_int64);
+  ```
+  Swift can now directly pass a raw pointer as the function argument:
+  ```swift
+  func decodeAsInt64(data: Data) -> Int64 {
+      data.withUnsafeBytes { (bytes: UnsafeRawBufferPointer) in
+          decode_int64(bytes.baseAddress!)
+      }
+  }
+  ```
+
 * [SE-0315][]:
 
   Type expressions and annotations can now include "type placeholders" which
@@ -34,6 +82,23 @@ Swift 5.6
 Swift 5.5
 ---------
 
+### 2021-09-20 (Xcode 13.0)
+
+* [SE-0323][]:
+
+  The main function is executed with `MainActor` isolation applied, so functions
+  and variables with `MainActor` isolation may be called and modified
+  synchronously from the main function. If the main function is annotated with a
+  global actor explicitly, it must be the main actor or an error is emitted. If
+  no global actor annotation is present, the main function is implicitly run on
+  the main actor.
+
+  The main function is executed synchronously up to the first suspension point.
+  Any tasks enqueued by initializers in Objective-C or C++ will run after the
+  main function runs to the first suspension point. At the suspension point, the
+  main function suspends and the tasks are executed according to the Swift
+  concurrency mechanisms.
+
 * [SE-0313][]:
 
   Parameters of actor type can be declared as `isolated`, which means that they
@@ -8694,6 +8759,8 @@ Swift 1.0
 [SE-0313]: <https://github.com/apple/swift-evolution/blob/main/proposals/0313-actor-isolation-control.md>
 [SE-0315]: <https://github.com/apple/swift-evolution/blob/main/proposals/0315-placeholder-types.md>
 [SE-0316]: <https://github.com/apple/swift-evolution/blob/main/proposals/0316-global-actors.md>
+[SE-0324]: <https://github.com/apple/swift-evolution/blob/main/proposals/0324-c-lang-pointer-arg-conversion.md>
+[SE-0323]: <https://github.com/apple/swift-evolution/blob/main/proposals/0323-async-main-semantics.md>
 
 [SR-75]: <https://bugs.swift.org/browse/SR-75>
 [SR-106]: <https://bugs.swift.org/browse/SR-106>

CMakeLists.txt

@@ -1,5 +1,8 @@
 cmake_minimum_required(VERSION 3.19.6)
 
+
+#  set_property(GLOBAL PROPERTY GLOBAL_DEPENDS_DEBUG_MODE 1)
+
 # TODO: Fix RPATH usage to be CMP0068 compliant
 # Disable Policy CMP0068 for CMake 3.9
 # rdar://37725888
@@ -196,9 +199,13 @@ set(SWIFT_TOOLS_ENABLE_LTO OFF CACHE STRING "Build Swift tools with LTO. One
     no effect on the target libraries (the standard library and the runtime).")
 
 # NOTE: We do not currently support building libswift with the Xcode generator.
-cmake_dependent_option(SWIFT_TOOLS_ENABLE_LIBSWIFT
-  "Enable building libswift and linking libswift into the compiler itself." FALSE
-  "NOT CMAKE_GENERATOR STREQUAL \"Xcode\"" FALSE)
+cmake_dependent_option(LIBSWIFT_BUILD_MODE "How to build libswift. Possible values are
+    OFF:           the compiler is built without libswift
+    HOSTTOOLS:     libswift is built with a pre-installed toolchain
+    BOOTSTRAPPING: libswift is built with a 2-stage bootstrapping process
+    BOOTSTRAPPING-WITH-HOSTLIBS:   libswift is built with a 2-stage bootstrapping process,
+                   but the compiler links against the host system swift libs (macOS only)"
+  OFF "NOT CMAKE_GENERATOR STREQUAL \"Xcode\"" OFF)
 
 # The following only works with the Ninja generator in CMake >= 3.0.
 set(SWIFT_PARALLEL_LINK_JOBS "" CACHE STRING
@@ -390,13 +397,25 @@ option(SWIFT_CHECK_INCREMENTAL_COMPILATION
     "Check if incremental compilation works when compiling the Swift libraries"
     FALSE)
 
+option(SWIFT_ENABLE_ARRAY_COW_CHECKS
+    "Compile the stdlib with Array COW checks enabled (only relevant for assert builds)"
+    FALSE)
+
 option(SWIFT_REPORT_STATISTICS
     "Create json files which contain internal compilation statistics"
     FALSE)
 
-option(SWIFT_DISABLE_OBJC_INTEROP
-    "Disable Objective-C interoperability even on platforms what would normally have it"
-    FALSE)
+# Only Darwin platforms enable ObjC interop by default.
+if("${SWIFT_HOST_VARIANT_SDK}" MATCHES "(OSX|IOS*|TVOS*|WATCHOS*)")
+  set(SWIFT_STDLIB_ENABLE_OBJC_INTEROP_default TRUE)
+else()
+  set(SWIFT_STDLIB_ENABLE_OBJC_INTEROP_default FALSE)
+endif()
+
+# Used by stdlib/toolchain as well, so this cannot be in stdlib/CMakeLists.txt
+option(SWIFT_STDLIB_ENABLE_OBJC_INTEROP
+       "Should stdlib be built with Obj-C interop."
+       "${SWIFT_STDLIB_ENABLE_OBJC_INTEROP_default}")
 
 #
 # User-configurable experimental options.  Do not use in production builds.
@@ -487,7 +506,7 @@ endif()
 # Use dispatch as the system scheduler by default.
 # For convenience, we set this to false when concurrency is disabled.
 set(SWIFT_CONCURRENCY_USES_DISPATCH FALSE)
-if(SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY AND NOT SWIFT_STDLIB_SINGLE_THREADED_RUNTIME)
+if(SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY AND "${SWIFT_CONCURRENCY_GLOBAL_EXECUTOR}" STREQUAL "dispatch")
   set(SWIFT_CONCURRENCY_USES_DISPATCH TRUE)
 endif()
 
@@ -506,6 +525,18 @@ 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
 #
@@ -589,6 +620,20 @@ set(SWIFT_RUNTIME_OUTPUT_INTDIR "${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin")
 set(SWIFT_LIBRARY_OUTPUT_INTDIR "${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib")
 if("${SWIFT_NATIVE_SWIFT_TOOLS_PATH}" STREQUAL "")
   set(SWIFT_NATIVE_SWIFT_TOOLS_PATH "${SWIFT_RUNTIME_OUTPUT_INTDIR}")
+  set(SWIFT_EXEC_FOR_LIBSWIFT "${CMAKE_Swift_COMPILER}")
+elseif(LIBSWIFT_BUILD_MODE STREQUAL "BOOTSTRAPPING" OR LIBSWIFT_BUILD_MODE STREQUAL "BOOTSTRAPPING-WITH-HOSTLIBS")
+  # If cross-compiling we don't have to bootstrap. We can just use the previously
+  # built native swiftc to build libswift.
+  message(STATUS "Building libswift with native host tools instead of bootstrapping")
+  set(LIBSWIFT_BUILD_MODE "HOSTTOOLS")
+  set(SWIFT_EXEC_FOR_LIBSWIFT "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/swiftc")
+endif()
+
+if(LIBSWIFT_BUILD_MODE STREQUAL "HOSTTOOLS" OR LIBSWIFT_BUILD_MODE STREQUAL "BOOTSTRAPPING-WITH-HOSTLIBS")
+  if(SWIFT_ENABLE_ARRAY_COW_CHECKS)
+    message(STATUS "array COW checks disabled when building libswift with host libraries")
+    set(SWIFT_ENABLE_ARRAY_COW_CHECKS FALSE)
+  endif()
 endif()
 
 # This setting causes all CMakeLists.txt to automatically have
@@ -933,7 +978,7 @@ if(SWIFT_INCLUDE_TOOLS)
   message(STATUS "  Build type:     ${CMAKE_BUILD_TYPE}")
   message(STATUS "  Assertions:     ${LLVM_ENABLE_ASSERTIONS}")
   message(STATUS "  LTO:            ${SWIFT_TOOLS_ENABLE_LTO}")
-  message(STATUS "  libswift:       ${SWIFT_TOOLS_ENABLE_LIBSWIFT}")
+  message(STATUS "  libswift:       ${LIBSWIFT_BUILD_MODE}")
   message(STATUS "")
 else()
   message(STATUS "Not building host Swift tools")
@@ -1040,6 +1085,9 @@ if(SWIFT_ENABLE_DISPATCH)
   include(Libdispatch)
 endif()
 
+add_bootstrapping_target(0)
+add_bootstrapping_target(1)
+
 # Add all of the subdirectories, where we actually do work.
 
 ###############

README.md

@@ -17,15 +17,13 @@
 
 | **OS** | **Architecture** | **Build** |
 |---|:---:|:---:|
-|**[Ubuntu 16.04 ](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/ppc64le_ubuntu_16_04.json)** | PPC64LE |[![Build Status](https://ci-external.swift.org/job/oss-swift-5.1-RA-linux-ubuntu-16.04-ppc64le/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-5.1-RA-linux-ubuntu-16.04-ppc64le)|
-|**[Ubuntu 18.04](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/aarch64_ubuntu_18.04_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-18.04-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-18.04-aarch64)|
-|**[Ubuntu 20.04](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/aarch64_ubuntu_20.04_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-20.04-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-20.04-aarch64)|
-|**[CentOS 8 ](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/aarch64_centos_8_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-centos8-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-centos8-aarch64)|
-|**[Amazon Linux 2](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/aarch64_amazon_linux_2_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-amazon-linux-2-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-amazon-linux-2-aarch64)|
-|**[Android](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/x86_64_ubuntu_16_04_LTS_android.json)** | ARMv7 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android)|
-|**[Android](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/x86_64_ubuntu_16_04_LTS_android.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android-arm64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android-arm64)|
-|**[Windows 2019 (VS 2017)](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/x86_64_windows_2019.json)** | x86_64 | [![Build Status](https://ci-external.swift.org/job/oss-swift-windows-x86_64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-windows-x86_64)|
-|**[Windows 2019 (VS 2019)](https://github.com/apple/swift-community-hosted-continuous-integration/blob/master/nodes/x86_64_windows_2019_VS2019.json)** | x86_64 | [![Build Status](https://ci-external.swift.org/job/oss-swift-windows-x86_64-vs2019/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-windows-x86_64-vs2019)|
+|**[Ubuntu 16.04 ](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/ppc64le_ubuntu_16_04.json)** | PPC64LE |[![Build Status](https://ci-external.swift.org/job/oss-swift-5.1-RA-linux-ubuntu-16.04-ppc64le/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-5.1-RA-linux-ubuntu-16.04-ppc64le)|
+|**[Ubuntu 18.04](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/aarch64_ubuntu_18.04_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-18.04-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-18.04-aarch64)|
+|**[Ubuntu 20.04](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/aarch64_ubuntu_20.04_docker.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-20.04-aarch64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-ubuntu-20.04-aarch64)|
+|**[Android](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/x86_64_ubuntu_16_04_LTS_android.json)** | ARMv7 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android)|
+|**[Android](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/x86_64_ubuntu_16_04_LTS_android.json)** | AArch64 |[![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android-arm64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-android-arm64)|
+|**[Windows 2019 (VS 2017)](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/x86_64_windows_2019.json)** | x86_64 | [![Build Status](https://ci-external.swift.org/job/oss-swift-windows-x86_64/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-windows-x86_64)|
+|**[Windows 2019 (VS 2019)](https://github.com/apple/swift-community-hosted-continuous-integration/blob/main/nodes/x86_64_windows_2019_VS2019.json)** | x86_64 | [![Build Status](https://ci-external.swift.org/job/oss-swift-windows-x86_64-vs2019/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-windows-x86_64-vs2019)|
 
 ## Welcome to Swift
 

benchmark/CMakeLists.txt

@@ -59,7 +59,7 @@ set(SWIFT_BENCH_MODULES
     single-source/CharacterProperties
     single-source/Chars
     single-source/ClassArrayGetter
-    single-source/Codable
+    single-source/CodableTest
     single-source/Combos
     single-source/DataBenchmarks
     single-source/DeadArray
@@ -76,7 +76,7 @@ set(SWIFT_BENCH_MODULES
     single-source/DictionaryCopy
     single-source/DictionaryGroup
     single-source/DictionaryKeysContains
-    single-source/DictionaryLiteral
+    single-source/DictionaryLiteralTest
     single-source/DictionaryOfAnyHashableStrings
     single-source/DictionaryRemove
     single-source/DictionarySubscriptDefault
@@ -112,11 +112,11 @@ set(SWIFT_BENCH_MODULES
     single-source/LuhnAlgoLazy
     single-source/MapReduce
     single-source/Memset
-    single-source/Mirror
+    single-source/MirrorTest
     single-source/MonteCarloE
     single-source/MonteCarloPi
     single-source/NSDictionaryCastToSwift
-    single-source/NSError
+    single-source/NSErrorTest
     single-source/NSStringConversion
     single-source/NibbleSort
     single-source/NIOChannelPipeline
@@ -143,7 +143,7 @@ set(SWIFT_BENCH_MODULES
     single-source/ProtocolConformance
     single-source/ProtocolDispatch
     single-source/ProtocolDispatch2
-    single-source/Queue
+    single-source/QueueTest
     single-source/RC4
     single-source/RGBHistogram
     single-source/Radix2CooleyTukey
@@ -186,7 +186,7 @@ set(SWIFT_BENCH_MODULES
     single-source/StringSwitch
     single-source/StringTests
     single-source/StringWalk
-    single-source/Substring
+    single-source/SubstringTest
     single-source/Suffix
     single-source/SuperChars
     single-source/TwoSum

benchmark/README.md

@@ -199,7 +199,30 @@ benchmarks will be compiled with -Onone!**
 * `$ ./Benchmark_O --tags=Dictionary`
 * `$ ./Benchmark_O --skip-tags=unstable,skip,validation`
 
-### Note
+### Deterministic Hashing Requirement
+
+To run benchmarks, you'll need to disable randomized hash seeding by setting the
+`SWIFT_DETERMINISTIC_HASHING` environment variable to `1`. (You only need to do
+this when running the benchmark executables directly -- the driver script does
+this for you automatically.)
+
+* `$ env SWIFT_DETERMINISTIC_HASHING=1 ./Benchmark_O --num-iters=1 --num-samples=1`
+
+This makes for more stable results, by preventing random hash collision changes
+from affecting benchmark measurements. Benchmark measurements start by checking
+that deterministic hashing is enabled and they fail with a runtime trap when it
+isn't.
+
+If for some reason you want to run the benchmarks using standard randomized
+hashing, you can disable this check by passing the
+`--allow-nondeterministic-hashing` option to the executable.
+
+* `$ ./Benchmark_O --num-iters=1 --num-samples=1 --allow-nondeterministic-hashing`
+
+This will affect the reliability of measurements, so this is not recommended.
+
+### Benchmarking by Numbers
+
 As a shortcut, you can also refer to benchmarks by their ordinal numbers.
 These are printed out together with benchmark names and tags using the
 `--list` parameter. For a complete list of all available performance tests run
@@ -290,16 +313,18 @@ If needed you can multiply N by a fixed amount (e.g. `1...100*N`) to achieve thi
 // rdar://problem/00000000
 import TestsUtils
 
-public let YourTestName = BenchmarkInfo(
-  name: "YourTestName",
-  runFunction: run_YourTestName,
-  tags: [.regression])
+public let benchmarks = [
+  BenchmarkInfo(
+    name: "YourTestName",
+    runFunction: run_YourTestName,
+    tags: [.regression])
+]
 
 @inline(never)
-public func run_YourTestName(N: Int) {
+public func run_YourTestName(n: Int) {
     # Declare variables
 
-    for i in 1...N {
+    for i in 1...n {
         # Perform work
 
         # Verify work was done; break otherwise

benchmark/cmake/modules/AddSwiftBenchmarkSuite.cmake

@@ -683,7 +683,7 @@ function (swift_benchmark_compile_archopts)
           ${objcfile}
           "-o" "${OUTPUT_EXEC}"
         COMMAND
-        "codesign" "-f" "-s" "-" "${OUTPUT_EXEC}")
+        "${srcdir}/../utils/swift-darwin-postprocess.py" "${OUTPUT_EXEC}")
   else()
     # TODO: rpath.
     add_custom_command(

benchmark/cxx-source/CreateObjects.swift

@@ -16,14 +16,16 @@
 import TestsUtils
 import CxxCreateObjects
 
-public let CreateObjects = BenchmarkInfo(
-  name: "CreateObjects",
-  runFunction: run_CreateObjects,
-  tags: [.validation, .bridging])
+public let benchmarks = [
+  BenchmarkInfo(
+    name: "CreateObjects",
+    runFunction: run_CreateObjects,
+    tags: [.validation, .bridging])
+]
 
 @inline(never)
-public func run_CreateObjects(_ N: Int) {
-  for i in 0...(N * 10_000) {
+public func run_CreateObjects(_ n: Int) {
+  for i in 0...(n * 10_000) {
     let x = Int32(i)
     let f = CxxLoadableIntWrapper(value: x)
     blackHole(f)