[Sema] Resilience: Diagnose uses of init accessors in inlinable contexts if they are not marked as @usableFromInline

(cherry picked from commit 123068c)

Author: xedin

lib/Sema/ResilienceDiagnostics.cpp

@@ -63,6 +63,17 @@ bool TypeChecker::diagnoseInlinableDeclRefAccess(SourceLoc loc,
   auto *DC = where.getDeclContext();
   auto &Context = DC->getASTContext();
 
+  if (auto *init = dyn_cast<ConstructorDecl>(DC)) {
+    if (init->isDesignatedInit()) {
+      auto *storage = dyn_cast<AbstractStorageDecl>(D);
+      if (storage && storage->hasInitAccessor()) {
+        if (diagnoseInlinableDeclRefAccess(
+                loc, storage->getAccessor(AccessorKind::Init), where))
+          return true;
+      }
+    }
+  }
+
   ImportAccessLevel problematicImport = D->getImportAccessFrom(DC);
   if (problematicImport.has_value()) {
     auto SF = DC->getParentSourceFile();
@@ -111,7 +122,7 @@ bool TypeChecker::diagnoseInlinableDeclRefAccess(SourceLoc loc,
 
   // Swift 4.2 did not check accessor accessibility.
   if (auto accessor = dyn_cast<AccessorDecl>(D)) {
-    if (!Context.isSwiftVersionAtLeast(5))
+    if (!accessor->isInitAccessor() && !Context.isSwiftVersionAtLeast(5))
       downgradeToWarning = DowngradeToWarning::Yes;
   }
 

test/attr/attr_alwaysEmitIntoClient.swift

@@ -15,4 +15,31 @@ public func publicFunction() {}
   internalFunction() // expected-error {{global function 'internalFunction()' is internal and cannot be referenced from an '@_alwaysEmitIntoClient' function}}
   versionedFunction()
   publicFunction()
-}
+}
+
+public struct TestInitAccessors {
+  var _x: Int
+
+  public var x: Int {
+    @storageRestrictions(initializes: _x)
+    init { // expected-note 2 {{init acecssor for property 'x' is not '@usableFromInline' or public}}
+      self._x = newValue
+    }
+
+    get {
+      self._x
+    }
+
+     set {}
+   }
+
+   @_alwaysEmitIntoClient
+   public init(x: Int) {
+     self.x = 0 // expected-error {{init acecssor for property 'x' is internal and cannot be referenced from an '@_alwaysEmitIntoClient' function}}
+   }
+
+   @inlinable
+   public init() {
+     self.x = 0 // expected-error {{init acecssor for property 'x' is internal and cannot be referenced from an '@inlinable' function}}
+   }
+}