Merge branch 'master' into redeclaration-fixes

Author: DougGregor

CHANGELOG.md

@@ -6,6 +6,7 @@ CHANGELOG
 
 | Contents               |
 | :--------------------- |
+| [Swift 5.0](#swift-50) |
 | [Swift 4.2](#swift-42) |
 | [Swift 4.1](#swift-41) |
 | [Swift 4.0](#swift-40) |
@@ -20,6 +21,43 @@ CHANGELOG
 
 </details>
 
+Swift 5.0
+---------
+
+- [SR-419][]
+
+  In Swift 5 mode, when setting a property from within its own `didSet` or `willSet` observer, the observer will now only avoid being recursively called if the property is set on `self` (either implicitly or explicitly).
+
+  For example:
+  ```swift
+  class Node {
+    var children = [Node]()
+
+    var depth: Int {
+      didSet {
+        if depth < 0 {
+          // Will not recursively call didSet, as setting depth on self (same
+          // with `self.depth = 0`).
+          depth = 0
+        }
+
+        // Will call didSet for each of the children, as we're not setting the
+        // property on self (prior to Swift 5, this did not trigger property
+        // observers to be called again).
+        for child in children {
+          child.depth = depth + 1
+        }
+      }
+    }
+
+    init(depth: Int) {
+      self.depth = depth
+    }
+  }
+  ```
+
+**Add new entries to the top of this section, not here!**
+
 Swift 4.2
 ---------
 
@@ -55,7 +93,7 @@ Swift 4.2
 	conditionally conforms to `P`, will succeed when the conditional
 	requirements are met.
 
-**Add new entries to the top of this file, not here!**
+**Add new entries to the top of this section, not here!**
 
 Swift 4.1
 ---------
@@ -276,7 +314,7 @@ Swift 4.0
   CFHash and CFEqual as the implementation. This change applies even to "Swift
   3 mode", so if you were previously adding this conformance yourself, use
   `#if swift(>=3.2)` to restrict the extension to Swift 3.1 and below.
-  ([SR-2388](https://bugs.swift.org/browse/SR-2388))
+  ([SR-2388][])
 
 * [SE-0156][]
 
@@ -425,7 +463,7 @@ Swift 4.0
   slice[i..<j] = buffer[k..<l]
   ```
 
-* [SR-1529](https://bugs.swift.org/browse/SR-1529):
+* [SR-1529][]:
 
   Covariant method overrides are now fully supported, fixing many crashes
   and compile-time assertions when defining or calling such methods.
@@ -508,7 +546,7 @@ Swift 3.1
   side effects, leading to bugs when Swift code attempted to override
   `initialize`.
 
-* [SR-2394](https://bugs.swift.org/browse/SR-2394)
+* [SR-2394][]
 
   C functions that "return twice" are no longer imported into Swift. Instead,
   they are explicitly made unavailable, so attempting to reference them will
@@ -585,7 +623,7 @@ Swift 3.1
   is not guaranteed to work in future versions of Swift, and will
   now raise a warning.
 
-* [SR-1446](https://bugs.swift.org/browse/SR-1446)
+* [SR-1446][]
 
   Nested types may now appear inside generic types, and nested types may have their own generic parameters:
 
@@ -605,7 +643,7 @@ Swift 3.1
   extension OuterGeneric.InnerGeneric {}
   ```
 
-* [SR-1009](https://bugs.swift.org/browse/SR-1009):
+* [SR-1009][]:
 
   Constrained extensions allow same-type constraints between generic parameters and concrete types. This enables you to create extensions, for example, on `Array` with `Int` elements:
 
@@ -827,7 +865,7 @@ using the `.dynamicType` member to retrieve the type of an expression should mig
     var x2 = p as! [Int]
     ```
 
-* [SR-2131](https://bugs.swift.org/browse/SR-2131):
+* [SR-2131][]:
 
   The `hasPrefix` and `hasSuffix` functions now consider the empty string to be a prefix and suffix of all strings.
 
@@ -6915,3 +6953,11 @@ Swift 1.0
 [SE-0197]: <https://github.com/apple/swift-evolution/blob/master/proposals/0197-remove-where.md>
 [SE-0198]: <https://github.com/apple/swift-evolution/blob/master/proposals/0198-playground-quicklook-api-revamp.md>
 [SE-0199]: <https://github.com/apple/swift-evolution/blob/master/proposals/0199-bool-toggle.md>
+
+[SR-419]: <https://bugs.swift.org/browse/SR-419>
+[SR-1009]: <https://bugs.swift.org/browse/SR-1009>
+[SR-1446]: <https://bugs.swift.org/browse/SR-1446>
+[SR-1529]: <https://bugs.swift.org/browse/SR-1529>
+[SR-2131]: <https://bugs.swift.org/browse/SR-2131>
+[SR-2388]: <https://bugs.swift.org/browse/SR-2388>
+[SR-2394]: <https://bugs.swift.org/browse/SR-2394>

benchmark/scripts/Benchmark_QuickCheck.in

@@ -41,15 +41,16 @@ class QuickCheckResult(perf_test_driver.Result):
 
 class QuickCheckBenchmarkDriver(perf_test_driver.BenchmarkDriver):
 
-    def __init__(self, binary, xfail_list, num_iters):
+    def __init__(self, binary, xfail_list, num_iters, opt_levels):
         perf_test_driver.BenchmarkDriver.__init__(
             self, binary, xfail_list,
-            enable_parallel=True)
+            enable_parallel=True,
+            opt_levels=opt_levels)
         self.num_iters = num_iters
 
     def print_data_header(self, max_test_len):
-        fmt = '{:<%d}{:<10}{:}' % (max_test_len + 5)
-        print(fmt.format('Name', 'Result', 'RC Delta'))
+        fmt = '{:<%d}{:<10}' % (max_test_len + 5)
+        print(fmt.format('Name', 'Result'))
 
     # Propagate any data from this class that is needed for individual
     # tests. The reason this is needed is to avoid issues with attempting to
@@ -99,15 +100,21 @@ def parse_args():
     import argparse
     parser = argparse.ArgumentParser()
     parser.add_argument(
-        '-filter', type=str, default=None,
+        '--filter', type=str, default=None,
         help='Filter out any test that does not match the given regex')
-    parser.add_argument('-num-iters', type=int, default=2)
+    parser.add_argument('--num-iters', type=int, default=2)
+    default_opt_levels = perf_test_driver.BenchmarkDriver_OptLevels
+    parser.add_argument('--opt-level', choices=default_opt_levels)
     return parser.parse_args()
 
 
 if __name__ == "__main__":
     args = parse_args()
-    l = QuickCheckBenchmarkDriver(SWIFT_BIN_DIR, XFAIL_LIST, args.num_iters)
+    opt_levels = perf_test_driver.BenchmarkDriver_OptLevels
+    if args.opt_level is not None:
+        opt_levels = [args.opt_level]
+    l = QuickCheckBenchmarkDriver(SWIFT_BIN_DIR, XFAIL_LIST, args.num_iters,
+                                  opt_levels)
     if l.run(args.filter):
         sys.exit(0)
     else:

cmake/modules/AddSwift.cmake

@@ -333,8 +333,8 @@ function(_add_variant_swift_compile_flags
     list(APPEND result "-D" "INTERNAL_CHECKS_ENABLED")
   endif()
 
-  if (SWIFT_ENABLE_GUARANTEED_NORMAL_ARGUMENTS)
-    list(APPEND result "-Xfrontend" "-enable-guaranteed-normal-arguments")
+  if (NOT SWIFT_ENABLE_GUARANTEED_NORMAL_ARGUMENTS)
+    list(APPEND result "-Xfrontend" "-disable-guaranteed-normal-arguments")
   endif()
 
   if(SWIFT_ENABLE_RUNTIME_FUNCTION_COUNTERS)

docs/ABI/Mangling.rst

@@ -209,6 +209,7 @@ Entities
   entity-spec ::= decl-name label-list? type 'v' ACCESSOR                           // variable
   entity-spec ::= decl-name type 'fp'                                               // generic type parameter
   entity-spec ::= decl-name type 'fo'                                               // enum element (currently not used)
+  entity-spec ::= identifier 'Qa'                                                   // associated type declaration
 
   ACCESSOR ::= 'm'                           // materializeForSet
   ACCESSOR ::= 's'                           // setter

docs/RefcountingStates.graffle

@@ -170,3 +170,23 @@ The standard library utilizes thread local storage (TLS) to cache expensive comp
 3. If the field is not trivially destructable, update `_destroyTLS` to properly destroy the value.
 
 See [ThreadLocalStorage.swift](https://github.com/apple/swift/blob/master/stdlib/public/core/ThreadLocalStorage.swift) for more details.
+
+## Productivity Hacks
+
+### Be a Ninja
+
+To *be* a productivity ninja, one must *use* `ninja`. `ninja` can be invoked inside the swift build directory, e.g. `<path>/build/Ninja-ReleaseAssert/swift-macosx-x86_64/`. Running `ninja` (which is equivalent to `ninja all`) will build the local swift, stdlib and overlays. It doesn’t necessarily build all the testing infrastructure, benchmarks, etc.
+
+`ninja -t targets` gives a list of all possible targets to pass to ninja. This is useful for grepping.
+
+For this example, we will figure out how to quickly iterate on a change to the standard library to fix 32-bit build errors while building on a 64-bit host, suppressing warnings along the way.
+
+`ninja -t targets | grep stdlib | grep i386` will output many targets, but at the bottom we see `swift-stdlib-iphonesimulator-i386`, which looks like a good first step. This target will just build i386 parts and not waste our time also building the 64-bit stdlib, overlays, etc.
+
+Going further, ninja can spawn a web browser for you to navigate dependencies and rules. `ninja -t browse swift-stdlib-iphonesimulator-i386`  will open a webpage with hyperlinks for all related targets. “target is built using” lists all this target’s dependencies, while “dependent edges build” list all the targets that depend directly on this.
+
+Clicking around a little bit, we can find `lib/swift/iphonesimulator/i386/libswiftCore.dylib` as a commonly-depended-upon target. This will perform just what is needed to compile the standard library for i386 and nothing else.
+
+Going further, for various reasons the standard library has lots of warnings. This is actively being addressed, but fixing all of them may require language features, etc. In the mean time, let’s suppress warnings in our build so that we just see the errors. `ninja -nv lib/swift/iphonesimulator/i386/libswiftCore.dylib` will show us the actual commands ninja will issue to build the i386 stdlib. (You’ll notice that an incremental build here is merely 3 commands as opposed to ~150 for `swift-stdlib-iphonesimulator-i386`).
+
+Copy the invocation that has  ` -o <build-path>/swift-macosx-x86_64/stdlib/public/core/iphonesimulator/i386/Swift.o`, so that we can perform the actual call to swiftc ourselves. Tack on `-suppress-warnings` at the end, and now we have the command to just build `Swift.o` for i386 while only displaying the actual errors.

docs/StandardLibraryProgrammersManual.md

@@ -74,7 +74,9 @@ argument to `x86` and run
 VsDevCmd -arch=x86
 ```
 
-- Then adapt the following command and run it.
+- Then adapt the following command and run it. Make sure to use forward slashes 
+  (`/`) instead of backslashes (`\`) as the path separators. `clang` breaks 
+  with backslashed paths.
 ```cmd
 set swift_source_dir=path-to-directory-containing-all-cloned-repositories
 ```
@@ -113,7 +115,14 @@ cmake -G "Ninja"^
  -DLLVM_TARGETS_TO_BUILD=X86^
  "%swift_source_dir%/llvm"
 popd
-cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/llvm-windows-amd64"
+cmake --build "%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"
+```
+- Store the LLVM `bin` directory in an environment variable so it can be used
+  to build Swift. Assuming you followed the instructions exactly, the path
+  below is correct, but it may be different based on your build variant and
+  platform, so double check.
+```cmd
+set llvm_bin_dir="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64/bin"
 ```
 
 ### 7. Build Swift
@@ -122,8 +131,8 @@ cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/llvm-windows-amd64"
 - You may need to adjust the `SWIFT_WINDOWS_LIB_DIRECTORY` parameter depending on
   your target platform or Windows SDK version.
 ```cmd
-mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
-pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
+mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
+pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
 cmake -G "Ninja" "%swift_source_dir%/swift"^
  -DCMAKE_BUILD_TYPE=Debug^
  -DSWIFT_PATH_TO_CMARK_SOURCE="%swift_source_dir%/cmark"^
@@ -141,13 +150,13 @@ cmake -G "Ninja" "%swift_source_dir%/swift"^
  -DICU_I18N_LIB_NAME="icuin"^
  -DSWIFT_INCLUDE_DOCS=FALSE^
  -DSWIFT_INCLUDE_TESTS=FALSE^
- -DCMAKE_C_COMPILER="<path-to-llvm-bin>/clang-cl.exe"^
- -DCMAKE_CXX_COMPILER="<path-to-llvm-bin>/bin/clang-cl.exe"^
+ -DCMAKE_C_COMPILER="%llvm_bin_dir%/clang-cl.exe"^
+ -DCMAKE_CXX_COMPILER="%llvm_bin_dir%/clang-cl.exe"^
  -DCMAKE_C_FLAGS="-fms-compatibility-version=19.00 /Z7"^
  -DCMAKE_CXX_FLAGS="-fms-compatibility-version=19.00 -Z7" ^
  -DSWIFT_BUILD_RUNTIME_WITH_HOST_COMPILER=FALSE
 popd
-cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
+cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
 ```
 
 - To create a Visual Studio project, you'll need to change the generator and,
@@ -168,13 +177,13 @@ cmake -G "Visual Studio 15" "%swift_source_dir%/swift"^
 Follow instructions 1-6 for `clang-cl`, but run the following instead to build Swift
 
 ```cmd
-mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
-pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
+mkdir "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
+pushd "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
 cmake -G "Ninja" "%swift_source_dir%/swift"^
  -DCMAKE_BUILD_TYPE=Debug^
  -DSWIFT_PATH_TO_CMARK_SOURCE="%swift_source_dir%/cmark"^
- -DSWIFT_PATH_TO_CMARK_BUILD="%swift_source_dir%/build/Ninja-DebugAssert/cmark-windows-amd64"^
- -DSWIFT_CMARK_LIBRARY_DIR="%swift_source_dir%/build/Ninja-DebugAssert/cmark-windows-amd64/src"^
+ -DSWIFT_PATH_TO_CMARK_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64"^
+ -DSWIFT_CMARK_LIBRARY_DIR="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/cmark-windows-amd64/src"^
  -DSWIFT_PATH_TO_LLVM_SOURCE="%swift_source_dir%/llvm"^
  -DSWIFT_PATH_TO_LLVM_BUILD="%swift_source_dir%/build/Ninja-RelWithDebInfoAssert/llvm-windows-amd64"^
  -DSWIFT_PATH_TO_CLANG_SOURCE="%swift_source_dir%/llvm/tools/clang"^
@@ -190,5 +199,5 @@ cmake -G "Ninja" "%swift_source_dir%/swift"^
  -DSWIFT_BUILD_DYNAMIC_SDK_OVERLAY=FALSE^
  -DSWIFT_BUILD_RUNTIME_WITH_HOST_COMPILER=FALSE
 popd
-cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64/ninja"
+cmake --build "%swift_source_dir%/build/Ninja-DebugAssert/swift-windows-amd64"
 ```