Merge pull request #4695 from swiftwasm/release/5.7

[pull] swiftwasm-release/5.7 from release/5.7

Author: kateinoigakukun

lib/AST/ASTPrinter.cpp

@@ -156,7 +156,6 @@ PrintOptions PrintOptions::printSwiftInterfaceFile(ModuleDecl *ModuleToPrint,
       PrintOptions::FunctionRepresentationMode::Full;
   result.AlwaysTryPrintParameterLabels = true;
   result.PrintSPIs = printSPIs;
-  result.DesugarExistentialConstraint = true;
 
   // We should print __consuming, __owned, etc for the module interface file.
   result.SkipUnderscoredKeywords = false;

lib/AST/ExistentialGeneralization.cpp

@@ -267,10 +267,14 @@ class Generalizer : public CanTypeVisitor<Generalizer, Type> {
 ExistentialTypeGeneralization
 ExistentialTypeGeneralization::get(Type rawType) {
   assert(rawType->isAnyExistentialType());
-  assert(!rawType->hasTypeParameter());
 
   // Canonicalize.  We need to generalize the canonical shape of the
   // type or else generalization parameters won't match up.
+  //
+  // TODO: in full generality, do we need to do *contextual*
+  // canonicalization in order to avoid introducing non-canonical
+  // parameters?  (That is, do we need a contextual generic
+  // signature if given an interface type?)
   CanType type = rawType->getCanonicalType();
 
   Generalizer generalizer(type->getASTContext());

test/Interpreter/parameterized_existentials.swift

@@ -44,5 +44,14 @@ ParameterizedProtocolsTestSuite.test("casting") {
   expectEqual(a.value, b.value)
 }
 
+// rdar://96571508
+struct ErasingHolder<T> {
+  let box: any Holder<T>
+}
+ParameterizedProtocolsTestSuite.test("casting") {
+  let a = ErasingHolder(box: IntHolder(value: 5))
+  expectEqual(a.box.value, 5)
+}
+
 runAllTests()
 

test/ModuleInterface/existential-any.swift

@@ -44,5 +44,10 @@ public protocol ProtocolTypealias {
   typealias A = P
 }
 
-// CHECK: public func dependentExistential<T>(value: (T) -> main.P) where T : main.ProtocolTypealias
+// CHECK: public func dependentExistential<T>(value: (T) -> T.A) where T : main.ProtocolTypealias
 public func dependentExistential<T: ProtocolTypealias>(value: (T) -> T.A) {}
+
+public typealias Composition = ProtocolTypealias & P
+
+// CHECK: public func optionalComposition(value: main.Composition?)
+public func optionalComposition(value: Composition?) {}