From a55dec28b9fc05f1e4cd5d6bbad8bb7b453b32c7 Mon Sep 17 00:00:00 2001
From: Krasnoriadtseva Anastasiia <anstkras@gmail.com>
Date: Tue, 26 May 2020 12:53:16 +0300
Subject: [PATCH] [FIR] Fix infinite CFG traverse

---
 .../src/org/jetbrains/kotlin/fir/analysis/cfa/CfgUtils.kt    | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/CfgUtils.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/CfgUtils.kt
index 14712032e65..3e9ac3ef079 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/CfgUtils.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/cfa/CfgUtils.kt
@@ -31,6 +31,7 @@ fun <D> ControlFlowGraph.traverse(
     stack.addFirst(initialNode)
     while (stack.isNotEmpty()) {
         val node = stack.removeFirst()
+        visitedNodes.add(node)
         val previousNodes = when (direction) {
             TraverseDirection.Forward -> node.previousNodes
             TraverseDirection.Backward -> node.followingNodes
@@ -49,9 +50,7 @@ fun <D> ControlFlowGraph.traverse(
             TraverseDirection.Backward -> node.previousNodes
         }
 
-        followingNodes.forEach {
-            stack.addFirst(it)
-        }
+        followingNodes.filterNot { visitedNodes.contains(it) }.forEach { stack.addFirst(it) }
     }
 }