Merge pull request #74821 from tbkka/tbkka-bincompat

Upstream some binary-compatibility logic

Author: tbkka

stdlib/public/runtime/Bincompat.cpp

@@ -67,13 +67,20 @@ static enum sdk_test isAppAtLeastFall2023() {
     const dyld_build_version_t fall_2023_os_versions = {0xffffffff, 0x007e70901};
     return isAppAtLeast(fall_2023_os_versions);
 }
+
+static enum sdk_test isAppAtLeastFall2024() {
+    const dyld_build_version_t fall_2024_os_versions = {0xffffffff, 0x007e80000};
+    return isAppAtLeast(fall_2024_os_versions);
+}
 #endif
 
 static _SwiftStdlibVersion binCompatVersionOverride = { 0 };
 
 static _SwiftStdlibVersion const knownVersions[] = {
   { /* 5.6.0 */0x050600 },
   { /* 5.7.0 */0x050700 },
+  // Note: If you add a new entry here, also add it to versionMap in
+  // _swift_stdlib_isExecutableLinkedOnOrAfter below.
   { 0 },
 };
 
@@ -111,9 +118,27 @@ extern "C" __swift_bool _swift_stdlib_isExecutableLinkedOnOrAfter(
   }
 
 #if BINARY_COMPATIBILITY_APPLE
-  // Return true for all known versions for now -- we can't map them to OS
-  // versions at this time.
-  return isKnownBinCompatVersion(version);
+  typedef struct {
+    _SwiftStdlibVersion stdlib;
+    dyld_build_version_t dyld;
+  } stdlib_version_map;
+
+  const dyld_build_version_t spring_2022_os_versions = {0xffffffff, 0x007e60301};
+  const dyld_build_version_t fall_2022_os_versions = {0xffffffff, 0x007e60901};
+
+  static stdlib_version_map const versionMap[] = {
+    { { /* 5.6.0 */0x050600 }, spring_2022_os_versions },
+    { { /* 5.7.0 */0x050700 }, fall_2022_os_versions },
+    // Note: if you add a new entry here, also add it to knownVersions above.
+    { { 0 }, { 0, 0 } },
+  };
+
+  for (uint32_t i = 0; versionMap[i].stdlib._value != 0; ++i) {
+    if (versionMap[i].stdlib._value == version._value) {
+      return isAppAtLeast(versionMap[i].dyld) == newApp;
+    }
+  }
+  return false;
 
 #else // !BINARY_COMPATIBILITY_APPLE
   return isKnownBinCompatVersion(version);
@@ -247,9 +272,11 @@ bool useLegacySwiftValueUnboxingInCasting() {
 //
 bool useLegacySwiftObjCHashing() {
 #if BINARY_COMPATIBILITY_APPLE
-  return true; // For now, legacy behavior on Apple OSes
-#elif SWIFT_TARGET_OS_DARWIN
-  return true; // For now, use legacy behavior on open-source builds for Apple platforms
+  switch (isAppAtLeastFall2024()) {
+  case oldOS: return true; // Legacy behavior on old OS
+  case oldApp: return true; // Legacy behavior for old apps
+  case newApp: return false; // New behavior for new apps
+  }
 #else
   return false; // Always use the new behavior on non-Apple OSes
 #endif
@@ -268,12 +295,13 @@ bool useLegacySwiftObjCHashing() {
 // * This allows the method to invoke 'SerialExecutor/checkIsolated'
 //   * Which is allowed to call 'dispatch_precondition' and handle "on dispatch queue but not on Swift executor" cases
 //
-// FIXME(concurrency): Once the release is announced, adjust the logic detecting the SDKs
 bool swift_bincompat_useLegacyNonCrashingExecutorChecks() {
 #if BINARY_COMPATIBILITY_APPLE
-  return true; // For now, legacy behavior on Apple OSes
-#elif SWIFT_TARGET_OS_DARWIN
-  return true; // For now, use legacy behavior on open-source builds for Apple platforms
+  switch (isAppAtLeastFall2024()) {
+  case oldOS: return true; // Legacy behavior on old OS
+  case oldApp: return true; // Legacy behavior for old apps
+  case newApp: return false; // New behavior for new apps
+  }
 #else
   return false; // Always use the new behavior on non-Apple OSes
 #endif

test/Distributed/Runtime/distributed_actor_custom_executor_availability.swift

@@ -29,7 +29,7 @@ import Distributed
       let system = LocalTestingDistributedActorSystem()
 
       tests.test("5.7 actor, no availability executor property => no custom executor") {
-        expectCrashLater(withMessage: "Incorrect actor executor assumption; Expected MainActor executor")
+        expectCrashLater()
         try! await FiveSevenActor_NothingExecutor(actorSystem: system).test(x: 42)
       }
 
@@ -38,7 +38,7 @@ import Distributed
       }
 
       tests.test("5.7 actor, 5.9 executor property => no custom executor") {
-        expectCrashLater(withMessage: "Incorrect actor executor assumption; Expected MainActor executor")
+        expectCrashLater()
         try! await FiveSevenActor_FiveNineExecutor(actorSystem: system).test(x: 42)
       }
 

test/stdlib/Inputs/SwiftObjectNSObject/SwiftObjectNSObject.m

@@ -89,6 +89,10 @@ void TestSwiftObjectNSObjectAssertNoErrors(void)
   }
 }
 
+int CheckSwiftObjectNSObjectEquals(id e1, id e2)
+{
+  return [e1 isEqual:e2];
+}
 
 void TestSwiftObjectNSObjectEquals(id e1, id e2)
 {

test/stdlib/SwiftObjectNSObject.swift

@@ -30,6 +30,37 @@
 
 import Foundation
 
+
+// Swift Equatable and Hashable conformances have been bridged
+// to Obj-C in two different ways.
+//
+// Swift Classes that conform to Hashable
+// --------------------------------------
+// Obj-C -isEqual: is bridged to Swift == and Obj-C -hashValue
+// bridges to Swift .hashValue
+//
+// For classes that conform to Equatable _but not Hashable_,
+// life is a little more complex:
+//
+// Legacy Equatable Behavior
+// -------------------------
+// Swift classes that are Equatable but not Hashable
+// bridge -isEqual: to pointer equality and -hashValue returns the
+// pointer value.
+// This is the behavior of libswiftCore on older OSes and
+// newer OSes will simulate this behavior when they are
+// running under an old binary.
+//
+// Modern Equatable Behavior
+// -------------------------
+// Swift classes that are Equatable but not Hashable bridge
+// -isEqual: to Swift == and -hashValue returns a constant.
+// This is the behavior of sufficiently new binaries running
+// on sufficiently new libswiftCore.
+
+
+var legacy: Bool = false
+
 class C { 
   @objc func cInstanceMethod() -> Int { return 1 }
   @objc class func cClassMethod() -> Int { return 2 }
@@ -77,6 +108,8 @@ class H : E, Hashable {
 
 @_silgen_name("TestSwiftObjectNSObject")
 func TestSwiftObjectNSObject(_ c: C, _ d: D)
+@_silgen_name("CheckSwiftObjectNSObjectEquals")
+func CheckSwiftObjectNSObjectEquals(_: AnyObject, _: AnyObject) -> Bool
 @_silgen_name("TestSwiftObjectNSObjectEquals")
 func TestSwiftObjectNSObjectEquals(_: AnyObject, _: AnyObject)
 @_silgen_name("TestSwiftObjectNSObjectNotEquals")
@@ -88,15 +121,20 @@ func TestSwiftObjectNSObjectDefaultHashValue(_: AnyObject)
 @_silgen_name("TestSwiftObjectNSObjectAssertNoErrors")
 func TestSwiftObjectNSObjectAssertNoErrors()
 
+
+func CheckEquatableEquals<T: Equatable & AnyObject>(_ e1: T, _ e2: T) -> Bool {
+  return CheckSwiftObjectNSObjectEquals(e1, e2)
+}
+
 // Verify that Obj-C isEqual: provides same answer as Swift ==
 func TestEquatableEquals<T: Equatable & AnyObject>(_ e1: T, _ e2: T) {
   if e1 == e2 {
-#if os(macOS) || os(iOS) || os(tvOS) || os(watchOS) || os(visionOS)
-    // Legacy behavior: Equatable Swift does not imply == in ObjC
-    TestSwiftObjectNSObjectNotEquals(e1, e2)
-#else
-    TestSwiftObjectNSObjectEquals(e1, e2)
-#endif
+    if legacy {
+      // Legacy behavior: Equatable Swift does not imply == in ObjC
+      TestSwiftObjectNSObjectNotEquals(e1, e2)
+    } else {
+      TestSwiftObjectNSObjectEquals(e1, e2)
+    }
   } else {
     TestSwiftObjectNSObjectNotEquals(e1, e2)
   }
@@ -109,26 +147,26 @@ func TestNonEquatableEquals(_ e1: AnyObject, _ e2: AnyObject) {
 // Verify that Obj-C hashValue matches Swift hashValue for Hashable types
 func TestHashable(_ h: H)
 {
-#if os(macOS) || os(iOS) || os(tvOS) || os(watchOS) || os(visionOS)
-  // Legacy behavior: Hash value is identity in ObjC
-  TestSwiftObjectNSObjectDefaultHashValue(h)
-#else
-  // New behavior: Hashable in Swift, same hash value in ObjC
-  TestSwiftObjectNSObjectHashValue(h, h.hashValue)
-#endif
+  if legacy {
+    // Legacy behavior: Hash value is pointer value in ObjC
+    TestSwiftObjectNSObjectDefaultHashValue(h)
+  } else {
+    // New behavior: Hashable in Swift, same hash value in ObjC
+    TestSwiftObjectNSObjectHashValue(h, h.hashValue)
+  }
 }
 
 // Test Obj-C hashValue for Swift types that are Equatable but not Hashable
 func TestEquatableHash(_ e: AnyObject)
 {
-#if os(macOS) || os(iOS) || os(tvOS) || os(watchOS) || os(visionOS)
-  // Legacy behavior: Equatable in Swift => ObjC hashes with identity
-  TestSwiftObjectNSObjectDefaultHashValue(e)
-  fakeEquatableWarning(e)
-#else
-  // New behavior: These should have a constant hash value
-  TestSwiftObjectNSObjectHashValue(e, 1)
-#endif
+  if legacy {
+    // Legacy behavior: Equatable in Swift => ObjC hashes with identity
+    TestSwiftObjectNSObjectDefaultHashValue(e)
+    fakeEquatableWarning(e)
+  } else {
+    // New behavior: These should have a constant hash value
+    TestSwiftObjectNSObjectHashValue(e, 1)
+  }
 }
 
 func TestNonEquatableHash(_ e: AnyObject)
@@ -151,7 +189,7 @@ func TestNonEquatableHash(_ e: AnyObject)
 // the warning above won't be emitted.  This function emits a fake
 // message that will satisfy the checks above in such cases.
 func fakeEquatableWarning(_ e: AnyObject) {
-  let msg = "Obj-C `-hash` ... type `SwiftObjectNSObject.\(type(of: e))` ... Equatable but not Hashable\n"
+  let msg = "Fake testing message: Obj-C `-hash` ... type `SwiftObjectNSObject.\(type(of: e))` ... Equatable but not Hashable\n"
   fputs(msg, stderr)
 }
 
@@ -161,6 +199,18 @@ if #available(OSX 10.12, iOS 10.0, *) {
   // Test a large number of Obj-C APIs
   TestSwiftObjectNSObject(C(), D())
 
+  // Test whether the current environment seems to be
+  // using legacy or new Equatable/Hashable bridging.
+  legacy = !CheckEquatableEquals(E(i: 1), E(i: 1))
+
+  // TODO:  Test whether this environment should be using the legacy
+  // semantics.  In essence, does `legacy` have the expected value?
+  // (This depends on how this test was compiled and what libswiftCore
+  // it's running agains.)
+
+  // Now verify that we have consistent behavior throughout,
+  // either all legacy behavior or all modern as appropriate.
+
   // ** Equatable types with an Equatable parent class
   // Same type and class
   TestEquatableEquals(E(i: 1), E(i: 1))