Harden diagnoseForcedCastExpr for lack of cast-to type

Author: ktoso

lib/SILGen/SILGenDistributed.cpp

@@ -281,8 +281,7 @@ void InitializeDistActorIdentity::dump(SILGenFunction &) const {
 
 bool SILGenFunction::shouldReplaceConstantForApplyWithDistributedThunk(
     FuncDecl *func) const {
-  auto isDistributedFuncOrAccessor =
-      func->isDistributed();
+  auto isDistributedFuncOrAccessor = func->isDistributed();
   if (auto acc = dyn_cast<AccessorDecl>(func)) {
     isDistributedFuncOrAccessor =
         acc->getStorage()->isDistributed();

lib/Sema/CSDiagnostics.cpp

@@ -9268,9 +9268,10 @@ bool NoopCheckedCast::diagnoseForcedCastExpr() const {
   }
 
   if (fromType->isEqual(toType)) {
-    auto castTypeRepr = expr->getCastTypeRepr();
-    emitDiagnostic(diag::forced_downcast_noop, toType)
-        .fixItRemove(SourceRange(diagLoc, castTypeRepr->getSourceRange().End));
+    auto diag = emitDiagnostic(diag::forced_downcast_noop, toType);
+    if (auto castTypeRepr = expr->getCastTypeRepr()) {
+      diag.fixItRemove(SourceRange(diagLoc, castTypeRepr->getSourceRange().End));
+    }
 
   } else {
     emitDiagnostic(diag::forced_downcast_coercion, fromType, toType)

lib/Sema/DerivedConformance/DerivedConformanceDistributedActor.cpp

@@ -335,7 +335,8 @@ deriveBodyDistributed_invokeHandlerOnReturn(AbstractFunctionDecl *afd,
     // If the SerializationRequirement requires it, we need to emit a cast:
     // metatype as! <<concrete SerializationRequirement.Type>>
     bool serializationRequirementIsAny =
-        metatypeParam->getInterfaceType()->getMetatypeInstanceType()->isAny();
+      serializationRequirementMetaTypeTy->getMetatypeInstanceType()->isEqual(
+            C.getAnyExistentialType());
 
     auto metatypeRef =
         new (C) DeclRefExpr(ConcreteDeclRef(metatypeParam), dloc, implicit);