Merge remote-tracking branch 'origin/master' into master-rebranch

Author: swift-ci

README.md

@@ -104,6 +104,14 @@ The required version of Xcode changes frequently, and is often a beta release.
 Check this document or the host information on <https://ci.swift.org> for the
 current required version.
 
+Swift's build tooling is meant to support spaces in the paths passed to them,
+but using spaces sometimes tickles bugs in Swift's build scripts or the tools
+they rely on. For example, [SR-13441](https://bugs.swift.org/browse/SR-13441)
+is caused by a space in the Xcode path used on macOS. If you see Swift's build
+tooling misbehave due to a space in a path, please
+[report the bug on the Swift bug tracker](https://swift.org/contributing/#reporting-bugs)
+and then change the path to work around it.
+
 You will also need [CMake](https://cmake.org) and [Ninja](https://ninja-build.org),
 which can be installed via a package manager:
 

lib/AST/ASTScopeLookup.cpp

@@ -519,7 +519,7 @@ bool BraceStmtScope::lookupLocalsOrMembers(ArrayRef<const ASTScopeImpl *>,
 bool PatternEntryInitializerScope::lookupLocalsOrMembers(
     ArrayRef<const ASTScopeImpl *>, DeclConsumer consumer) const {
   // 'self' is available within the pattern initializer of a 'lazy' variable.
-  auto *initContext = cast_or_null<PatternBindingInitializer>(
+  auto *initContext = dyn_cast_or_null<PatternBindingInitializer>(
       decl->getInitContext(0));
   if (initContext) {
     if (auto *selfParam = initContext->getImplicitSelfDecl()) {
@@ -816,7 +816,7 @@ Optional<bool> ClosureBodyScope::resolveIsCascadingUseForThisScope(
 Optional<bool> PatternEntryInitializerScope::resolveIsCascadingUseForThisScope(
     Optional<bool> isCascadingUse) const {
   auto *const initContext = getPatternEntry().getInitContext();
-  auto *PBI = cast_or_null<PatternBindingInitializer>(initContext);
+  auto *PBI = dyn_cast_or_null<PatternBindingInitializer>(initContext);
   auto *isd = PBI ? PBI->getImplicitSelfDecl() : nullptr;
 
   // 'self' is available within the pattern initializer of a 'lazy' variable.

validation-test/compiler_crashers_2_fixed/rdar67239650.swift

@@ -0,0 +1,24 @@
+// RUN: %target-swift-frontend -typecheck %s
+
+@_functionBuilder
+struct SillyBuilder {
+  static func buildBlock() -> () {}
+}
+
+struct SillyStruct {
+  init(@SillyBuilder _: () -> ()) {}
+}
+
+struct UsesSillyStruct {
+  var x: Int = 0
+
+  func foo() {
+    SillyStruct {
+      let fn = {
+        if true {
+          _ = x
+        }
+      }
+    }
+  }
+}