Merge pull request #17 from apple/master

merge

Author: JacobMao

.gitattributes

@@ -0,0 +1,2 @@
+*.swift.gyb linguist-language=Swift
+*.cpp.gyb linguist-language=C++

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,7 +2,7 @@
 Replace this paragraph with a description of your changes and rationale. Provide links to external references/discussions if appropriate.
 
 <!-- If this pull request resolves any bugs in the Swift bug tracker, provide a link: -->
-Resolves [SR-NNNN](https://bugs.swift.org/browse/SR-NNNN).
+Resolves SR-NNNN.
 
 <!--
 Before merging this pull request, you must run the Swift continuous integration tests.

.gitignore

@@ -24,6 +24,8 @@
 #==============================================================================#
 cscope.files
 cscope.out
+.vimrc
+tags
 
 #==============================================================================#
 # Directories to ignore (do not add trailing '/'s, they skip symlinks).

CHANGELOG.md

@@ -4,27 +4,130 @@ CHANGELOG
 <details>
 <summary>Note: This is in reverse chronological order, so newer entries are added to the top.</summary>
 
-| Contents               |
-| :--------------------- |
-| [Swift Next](#swift-next) |
-| [Swift 5.1](#swift-51) |
-| [Swift 5.0](#swift-50) |
-| [Swift 4.2](#swift-42) |
-| [Swift 4.1](#swift-41) |
-| [Swift 4.0](#swift-40) |
-| [Swift 3.1](#swift-31) |
-| [Swift 3.0](#swift-30) |
-| [Swift 2.2](#swift-22) |
-| [Swift 2.1](#swift-21) |
-| [Swift 2.0](#swift-20) |
-| [Swift 1.2](#swift-12) |
-| [Swift 1.1](#swift-11) |
-| [Swift 1.0](#swift-10) |
+| Version                | Released   | Toolchain   |
+| :--------------------- | :--------- | :---------- |
+| [Swift 5.2](#swift-52) |            |             |
+| [Swift 5.1](#swift-51) | 2019-09-20 | Xcode 11.0  |
+| [Swift 5.0](#swift-50) | 2019-03-25 | Xcode 10.2  |
+| [Swift 4.2](#swift-42) | 2018-09-17 | Xcode 10.0  |
+| [Swift 4.1](#swift-41) | 2018-03-29 | Xcode 9.3   |
+| [Swift 4.0](#swift-40) | 2017-09-19 | Xcode 9.0   |
+| [Swift 3.1](#swift-31) | 2017-03-27 | Xcode 8.3   |
+| [Swift 3.0](#swift-30) | 2016-09-13 | Xcode 8.0   |
+| [Swift 2.2](#swift-22) | 2016-03-21 | Xcode 7.3   |
+| [Swift 2.1](#swift-21) | 2015-10-21 | Xcode 7.1   |
+| [Swift 2.0](#swift-20) | 2015-09-17 | Xcode 7.0   |
+| [Swift 1.2](#swift-12) | 2015-04-08 | Xcode 6.3   |
+| [Swift 1.1](#swift-11) | 2014-12-02 | Xcode 6.1.1 |
+| [Swift 1.0](#swift-10) | 2014-09-15 | Xcode 6.0   |
 
 </details>
 
-Swift Next
-----------
+Swift 5.2
+---------
+
+* [SR-2790][]:
+
+  The compiler will now emit a warning when attempting to pass a temporary
+  pointer argument produced from an array, string, or inout argument to a
+  parameter which is known to escape it. This includes the various initializers 
+  for the `UnsafePointer`/`UnsafeBufferPointer` family of types, as well as
+  memberwise initializers.
+
+  ```swift
+  struct S {
+    var ptr: UnsafePointer<Int8>
+  }
+
+  func foo() {
+    var i: Int8 = 0
+    let ptr = UnsafePointer(&i)
+    // warning: initialization of 'UnsafePointer<Int8>' results in a 
+    // dangling pointer
+    
+    let s1 = S(ptr: [1, 2, 3]) 
+    // warning: passing '[Int8]' to parameter, but argument 'ptr' should be a
+    // pointer that outlives the call to 'init(ptr:)'
+    
+    let s2 = S(ptr: "hello")
+    // warning: passing 'String' to parameter, but argument 'ptr' should be a
+    // pointer that outlives the call to 'init(ptr:)'
+  }
+  ```
+
+  All 3 of the above examples are unsound because each argument produces a
+  temporary pointer only valid for the duration of the call they are passed to.
+  Therefore the returned value in each case references a dangling pointer.
+
+* [SR-2189][]:
+
+  The compiler now supports local functions whose default arguments capture
+  values from outer scopes.
+
+  ```swift
+  func outer(x: Int) -> (Int, Int) {
+    func inner(y: Int = x) -> Int {
+      return y
+    }
+
+    return (inner(), inner(y: 0))
+  }
+  ```
+
+* [SR-11429][]:
+
+  The compiler will now correctly strip argument labels from function references
+  used with the `as` operator in a function call. As a result, the `as` operator
+  can now be used to disambiguate a call to a function with argument labels. 
+  
+  ```swift
+  func foo(x: Int) {}
+  func foo(x: UInt) {}
+  
+  (foo as (Int) -> Void)(5)  // Calls foo(x: Int)
+  (foo as (UInt) -> Void)(5) // Calls foo(x: UInt)
+  ```
+  
+  Previously this was only possible for functions without argument labels.
+  
+  This change also means that a generic type alias can no longer be used to
+  preserve the argument labels of a function reference through the `as`
+  operator. The following is now rejected:
+  
+  ```swift
+  typealias Magic<T> = T
+  func foo(x: Int) {}
+  (foo as Magic)(x: 5) // error: Extraneous argument label 'x:' in call
+  ```
+  
+  The function value must instead be called without argument labels:
+  
+  ```swift
+  (foo as Magic)(5)
+  ```
+
+* [SR-11298][]:
+
+  A class-constrained protocol extension, where the extended protocol does
+  not impose a class constraint, will now infer the constraint implicitly.
+
+  ```swift
+  protocol Foo {}
+  class Bar: Foo {
+    var someProperty: Int = 0
+  }
+
+  // Even though 'Foo' does not impose a class constraint, it is automatically
+  // inferred due to the Self: Bar constraint.
+  extension Foo where Self: Bar {
+    var anotherProperty: Int {
+      get { return someProperty }
+      // As a result, the setter is now implicitly nonmutating, just like it would
+      // be if 'Foo' had a class constraint.
+      set { someProperty = newValue }
+    }
+  }
+  ```
 
 * [SE-0253][]:
 
@@ -51,7 +154,7 @@ Swift Next
 
 * [SR-4206][]:
 
-  A method override is no longer allowed to have a generic signature with 
+  A method override is no longer allowed to have a generic signature with
   requirements not imposed by the base method. For example:
 
   ```
@@ -88,6 +191,8 @@ Swift Next
 Swift 5.1
 ---------
 
+### 2019-09-20 (Xcode 11.0)
+
 * [SR-8974][]:
 
   Duplicate tuple element labels are no longer allowed, because it leads
@@ -7746,11 +7851,13 @@ Swift 1.0
 [SR-1529]: <https://bugs.swift.org/browse/SR-1529>
 [SR-2131]: <https://bugs.swift.org/browse/SR-2131>
 [SR-2176]: <https://bugs.swift.org/browse/SR-2176>
+[SR-2189]: <https://bugs.swift.org/browse/SR-2189>
 [SR-2388]: <https://bugs.swift.org/browse/SR-2388>
 [SR-2394]: <https://bugs.swift.org/browse/SR-2394>
 [SR-2608]: <https://bugs.swift.org/browse/SR-2608>
 [SR-2672]: <https://bugs.swift.org/browse/SR-2672>
 [SR-2688]: <https://bugs.swift.org/browse/SR-2688>
+[SR-2790]: <https://bugs.swift.org/browse/SR-2790>
 [SR-4206]: <https://bugs.swift.org/browse/SR-4206>
 [SR-4248]: <https://bugs.swift.org/browse/SR-4248>
 [SR-5581]: <https://bugs.swift.org/browse/SR-5581>
@@ -7765,3 +7872,5 @@ Swift 1.0
 [SR-8974]: <https://bugs.swift.org/browse/SR-8974>
 [SR-9043]: <https://bugs.swift.org/browse/SR-9043>
 [SR-9827]: <https://bugs.swift.org/browse/SR-9827>
+[SR-11298]: <https://bugs.swift.org/browse/SR-11298>
+[SR-11429]: <https://bugs.swift.org/browse/SR-11429>

CMakeLists.txt

@@ -11,14 +11,16 @@ endif()
 list(APPEND CMAKE_MODULE_PATH
     "${CMAKE_CURRENT_SOURCE_DIR}/cmake/modules")
 
+set(CMAKE_DISABLE_IN_SOURCE_BUILD YES)
+
 if(DEFINED CMAKE_JOB_POOLS)
   # CMake < 3.11 doesn't support CMAKE_JOB_POOLS. Manually set the property.
   set_property(GLOBAL PROPERTY JOB_POOLS "${CMAKE_JOB_POOLS}")
 else()
   # Make a job pool for things that can't yet be distributed
   cmake_host_system_information(
     RESULT localhost_logical_cores QUERY NUMBER_OF_LOGICAL_CORES)
-  set_property(GLOBAL PROPERTY JOB_POOLS local_jobs=${localhost_logical_cores})
+  set_property(GLOBAL APPEND PROPERTY JOB_POOLS local_jobs=${localhost_logical_cores})
   # Put linking in that category
   set(CMAKE_JOB_POOL_LINK local_jobs)
 endif()
@@ -125,7 +127,7 @@ set(SWIFT_ANALYZE_CODE_COVERAGE FALSE CACHE STRING
 # SWIFT_VERSION is deliberately /not/ cached so that an existing build directory
 # can be reused when a new version of Swift comes out (assuming the user hasn't
 # manually set it as part of their own CMake configuration).
-set(SWIFT_VERSION "5.1")
+set(SWIFT_VERSION "5.1.1")
 
 set(SWIFT_VENDOR "" CACHE STRING
     "The vendor name of the Swift compiler")
@@ -219,7 +221,7 @@ set(SWIFT_NATIVE_CLANG_TOOLS_PATH "" CACHE STRING
 set(SWIFT_NATIVE_SWIFT_TOOLS_PATH "" CACHE STRING
    "Path to the directory that contains Swift tools that are executable on the build machine")
 
-option(SWIFT_ENABLE_PARSEABLE_MODULE_INTERFACES
+option(SWIFT_ENABLE_MODULE_INTERFACES
        "Generate .swiftinterface files alongside .swiftmodule files"
        TRUE)
 
@@ -375,6 +377,10 @@ option(SWIFT_ENABLE_STDLIBCORE_EXCLUSIVITY_CHECKING
   "Build stdlibCore with exclusivity checking enabled"
   FALSE)
 
+option(SWIFT_ENABLE_EXPERIMENTAL_DIFFERENTIABLE_PROGRAMMING
+  "Enable experimental Swift differentiable programming features"
+  FALSE)
+
 #
 # End of user-configurable options.
 #
@@ -449,6 +455,10 @@ if(MSVC OR "${CMAKE_SIMULATE_ID}" STREQUAL MSVC)
   include(ClangClCompileRules)
 endif()
 
+if(CMAKE_C_COMPILER_ID MATCHES Clang)
+  add_compile_options($<$<OR:$<COMPILE_LANGUAGE:C>,$<COMPILE_LANGUAGE:CXX>>:-Werror=gnu>)
+endif()
+
 if(CMAKE_SYSTEM_NAME STREQUAL Darwin OR
     EXISTS "${SWIFT_PATH_TO_LIBDISPATCH_SOURCE}")
   set(SWIFT_BUILD_SYNTAXPARSERLIB_default TRUE)
@@ -962,17 +972,14 @@ if(SWIFT_NEED_EXPLICIT_LIBDISPATCH)
     set(SWIFT_LIBDISPATCH_C_COMPILER ${CMAKE_C_COMPILER})
     set(SWIFT_LIBDISPATCH_CXX_COMPILER ${CMAKE_CXX_COMPILER})
   elseif(${CMAKE_SYSTEM_NAME} STREQUAL ${CMAKE_HOST_SYSTEM_NAME})
-    get_target_property(CLANG_LOCATION clang LOCATION)
-    get_filename_component(CLANG_LOCATION ${CLANG_LOCATION} DIRECTORY)
-
     if(CMAKE_SYSTEM_NAME STREQUAL Windows)
       set(SWIFT_LIBDISPATCH_C_COMPILER
-          ${CLANG_LOCATION}/clang-cl${CMAKE_EXECUTABLE_SUFFIX})
+          $<TARGET_FILE_DIR:clang>/clang-cl${CMAKE_EXECUTABLE_SUFFIX})
       set(SWIFT_LIBDISPATCH_CXX_COMPILER
-          ${CLANG_LOCATION}/clang-cl${CMAKE_EXECUTABLE_SUFFIX})
+          $<TARGET_FILE_DIR:clang>/clang-cl${CMAKE_EXECUTABLE_SUFFIX})
     else()
-      set(SWIFT_LIBDISPATCH_C_COMPILER ${CLANG_LOCATION}/clang)
-      set(SWIFT_LIBDISPATCH_CXX_COMPILER ${CLANG_LOCATION}/clang++)
+      set(SWIFT_LIBDISPATCH_C_COMPILER $<TARGET_FILE_DIR:clang>/clang)
+      set(SWIFT_LIBDISPATCH_CXX_COMPILER $<TARGET_FILE_DIR:clang>/clang++)
     endif()
   else()
     message(SEND_ERROR "libdispatch requires a newer clang compiler (${CMAKE_C_COMPILER_VERSION} < 3.9)")
@@ -996,6 +1003,7 @@ if(SWIFT_NEED_EXPLICIT_LIBDISPATCH)
                         -DCMAKE_CXX_COMPILER=${SWIFT_LIBDISPATCH_CXX_COMPILER}
                         -DCMAKE_CXX_FLAGS=${CMAKE_CXX_FLAGS}
                         -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}
+                        -DCMAKE_INSTALL_LIBDIR=lib
                         -DCMAKE_INSTALL_PREFIX=<INSTALL_DIR>
                         -DCMAKE_LINKER=${CMAKE_LINKER}
                         -DCMAKE_RANLIB=${CMAKE_RANLIB}
@@ -1088,12 +1096,6 @@ endif()
 # declares the swift-stdlib-* set of targets. These targets will then
 # implicitly depend on any targets declared with IS_STDLIB.
 #
-# One such library that declares IS_STDLIB is SwiftSyntax, living in
-# tools/SwiftSyntax. If we include stdlib/ after tools/,
-# the swift-stdlib-* set of targets will not have been generated yet,
-# causing the implicit dependency for SwiftSyntax to silently not be
-# created. This then will cause SwiftSyntax to fail to build.
-#
 # https://bugs.swift.org/browse/SR-5975
 if(SWIFT_BUILD_STDLIB)
   add_subdirectory(stdlib)
@@ -1118,7 +1120,7 @@ add_subdirectory(include)
 
 if(SWIFT_INCLUDE_TOOLS)
   add_subdirectory(lib)
-  
+
   # Always include this after including stdlib/!
   # Refer to the large comment above the add_subdirectory(stdlib) call.
   # https://bugs.swift.org/browse/SR-5975
@@ -1127,6 +1129,8 @@ endif()
 
 add_subdirectory(utils)
 
+add_subdirectory(userdocs)
+
 if ("${CMAKE_SYSTEM_NAME}" STREQUAL "Darwin")
   if(SWIFT_BUILD_PERF_TESTSUITE)
     add_subdirectory(benchmark)