diff --git a/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JavaNullabilityWarningsChecker.kt b/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JavaNullabilityWarningsChecker.kt
index 72ae703860f..4b2d6ea83b8 100644
--- a/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JavaNullabilityWarningsChecker.kt
+++ b/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/JavaNullabilityWarningsChecker.kt
@@ -108,7 +108,7 @@ class JavaNullabilityWarningsChecker : AdditionalTypeChecker {
                             if (WhenChecker.getEnumMissingCases(expression, context, enumClassDescriptor).isEmpty()
                                 && !WhenChecker.containsNullCase(expression, context)) {
 
-                                c.trace.report(ErrorsJvm.WHEN_ENUM_CAN_BE_NULL_IN_JAVA.on(expression.getSubjectExpression()))
+                                c.trace.report(ErrorsJvm.WHEN_ENUM_CAN_BE_NULL_IN_JAVA.on(expression.subjectExpression!!))
                             }
                         }
                     }
diff --git a/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/TraitDefaultMethodCallChecker.kt b/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/TraitDefaultMethodCallChecker.kt
index 9a7be614980..7234845635b 100644
--- a/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/TraitDefaultMethodCallChecker.kt
+++ b/compiler/frontend.java/src/org/jetbrains/kotlin/resolve/jvm/checkers/TraitDefaultMethodCallChecker.kt
@@ -43,7 +43,7 @@ class TraitDefaultMethodCallChecker : CallChecker {
             if (classifier != null && DescriptorUtils.isInterface(classifier)) {
                 context.trace.report(
                         ErrorsJvm.INTERFACE_CANT_CALL_DEFAULT_METHOD_VIA_SUPER.on(
-                                PsiTreeUtil.getParentOfType(resolvedCall.getCall().getCallElement(), KtExpression::class.java)
+                                PsiTreeUtil.getParentOfType(resolvedCall.call.callElement, KtExpression::class.java)!!
                         )
                 )
             }
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationResolver.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationResolver.kt
index 9a66aa35f58..e46db2ef415 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationResolver.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/DeclarationResolver.kt
@@ -102,7 +102,7 @@ class DeclarationResolver(
                     val reportAt =
                             if (declarationOrPackageDirective is KtPackageDirective) declarationOrPackageDirective.getNameIdentifier()
                             else declarationOrPackageDirective
-                    trace.report(Errors.REDECLARATION.on(reportAt, fqName.shortName().asString()))
+                    trace.report(Errors.REDECLARATION.on(reportAt!!, fqName.shortName().asString()))
                 }
             }
         }
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/TypeResolver.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/TypeResolver.kt
index bf0c61240eb..537160f6b34 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/TypeResolver.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/TypeResolver.kt
@@ -307,7 +307,7 @@ class TypeResolver(
 
         val arguments = resolveTypeProjections(c, ErrorUtils.createErrorType("No type").constructor, type.typeArguments)
         if (!arguments.isEmpty()) {
-            c.trace.report(WRONG_NUMBER_OF_TYPE_ARGUMENTS.on(type.getTypeArgumentList(), 0))
+            c.trace.report(WRONG_NUMBER_OF_TYPE_ARGUMENTS.on(type.typeArgumentList!!, 0))
         }
 
         val containing = typeParameter.containingDeclaration
@@ -552,10 +552,10 @@ class TypeResolver(
                     val parameterDescriptor = constructor.parameters[i]
                     if (kind != INVARIANT && parameterDescriptor.variance != INVARIANT) {
                         if (kind == parameterDescriptor.variance) {
-                            c.trace.report(REDUNDANT_PROJECTION.on(argumentElement, constructor.getDeclarationDescriptor()))
+                            c.trace.report(REDUNDANT_PROJECTION.on(argumentElement, constructor.declarationDescriptor!!))
                         }
                         else {
-                            c.trace.report(CONFLICTING_PROJECTION.on(argumentElement, constructor.getDeclarationDescriptor()))
+                            c.trace.report(CONFLICTING_PROJECTION.on(argumentElement, constructor.declarationDescriptor!!))
                         }
                     }
                 }
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tasks/TracingStrategyForImplicitConstructorDelegationCall.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tasks/TracingStrategyForImplicitConstructorDelegationCall.kt
index 30da5b14ffb..d5d76abdbad 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tasks/TracingStrategyForImplicitConstructorDelegationCall.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/calls/tasks/TracingStrategyForImplicitConstructorDelegationCall.kt
@@ -59,7 +59,7 @@ class TracingStrategyForImplicitConstructorDelegationCall(
     }
 
     override fun unresolvedReference(trace: BindingTrace) {
-        trace.report(UNRESOLVED_REFERENCE.on(calleeExpression, calleeExpression))
+        trace.report(UNRESOLVED_REFERENCE.on(calleeExpression!!, calleeExpression))
     }
 
     override fun <D : CallableDescriptor> unresolvedReferenceWrongReceiver(trace: BindingTrace, candidates: Collection<ResolvedCall<D>>) {
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt
index 62e79d237bb..662dc21d5b6 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/resolve/lazy/descriptors/LazyClassMemberScope.kt
@@ -107,8 +107,7 @@ open class LazyClassMemberScope(
             }
 
             override fun conflict(fromSuper: CallableMemberDescriptor, fromCurrent: CallableMemberDescriptor) {
-                val declaration = DescriptorToSourceUtils.descriptorToDeclaration(fromCurrent) as KtDeclaration?
-                assert(declaration != null) { "fromCurrent can not be a fake override" }
+                val declaration = DescriptorToSourceUtils.descriptorToDeclaration(fromCurrent) as? KtDeclaration ?: error("fromCurrent can not be a fake override")
                 trace.report(Errors.CONFLICTING_OVERLOADS.on(declaration, fromCurrent, fromCurrent.getContainingDeclaration().getName().asString()))
             }
         })
diff --git a/compiler/frontend/src/org/jetbrains/kotlin/types/expressions/FunctionsTypingVisitor.kt b/compiler/frontend/src/org/jetbrains/kotlin/types/expressions/FunctionsTypingVisitor.kt
index 71ab7060104..e802defef3c 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/types/expressions/FunctionsTypingVisitor.kt
+++ b/compiler/frontend/src/org/jetbrains/kotlin/types/expressions/FunctionsTypingVisitor.kt
@@ -63,7 +63,7 @@ internal class FunctionsTypingVisitor(facade: ExpressionTypingInternals) : Expre
             }
 
             if (function.getName() != null) {
-                context.trace.report(ANONYMOUS_FUNCTION_WITH_NAME.on(function.getNameIdentifier()))
+                context.trace.report(ANONYMOUS_FUNCTION_WITH_NAME.on(function.nameIdentifier!!))
             }
 
             for (parameter in function.getValueParameters()) {
diff --git a/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt b/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
index 55ab22a4bd8..13a7313b289 100644
--- a/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
+++ b/js/js.frontend/src/org/jetbrains/kotlin/js/resolve/nativeAnnotationCheckers.kt
@@ -79,7 +79,7 @@ internal abstract class AbstractNativeIndexerChecker(
             if (firstParamClassDescriptor != builtIns.string &&
                 !DescriptorUtils.isSubclass(firstParamClassDescriptor, builtIns.number)
             ) {
-                diagnosticHolder.report(ErrorsJs.NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER.on(declaration.valueParameters.firstOrNull(), indexerKind))
+                diagnosticHolder.report(ErrorsJs.NATIVE_INDEXER_KEY_SHOULD_BE_STRING_OR_NUMBER.on(declaration.valueParameters.first(), indexerKind))
             }
         }