From 07feb2185b6d152cdad1ebd8f29b3e19189c8173 Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Wed, 1 Jul 2020 18:50:11 +0300
Subject: [PATCH] Fix exception in FirExposedVisibilityChecker

---
 .../checkers/declaration/FirExposedVisibilityChecker.kt       | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExposedVisibilityChecker.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExposedVisibilityChecker.kt
index 695852ac7f0..af9246cbc20 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExposedVisibilityChecker.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/declaration/FirExposedVisibilityChecker.kt
@@ -96,8 +96,8 @@ object FirExposedVisibilityChecker : FirMemberDeclarationChecker() {
     private fun checkFunction(declaration: FirFunction<*>, reporter: DiagnosticReporter) {
         val functionVisibility = (declaration as FirMemberDeclaration).firEffectiveVisibility(declaration.session)
         if (declaration !is FirConstructor) {
-            val restricting = declaration.returnTypeRef.coneType
-                .leastPermissiveDescriptor(declaration.session, functionVisibility)
+            val restricting = declaration.returnTypeRef.coneTypeSafe<ConeKotlinType>()
+                ?.leastPermissiveDescriptor(declaration.session, functionVisibility)
             if (restricting != null) {
                 reporter.reportExposure(
                     FirErrors.EXPOSED_FUNCTION_RETURN_TYPE,