diff --git a/compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/ClientUtils.kt b/compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/ClientUtils.kt
index 10b8fa7cae2..3f162df5f8f 100644
--- a/compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/ClientUtils.kt
+++ b/compiler/daemon/daemon-common/src/org/jetbrains/kotlin/daemon/common/ClientUtils.kt
@@ -52,7 +52,7 @@ fun walkDaemons(registryDir: File,
     return registryDir.walk()
             .map { Pair(it, portExtractor(it.name)) }
             .filter { it.second != null && filter(it.first, it.second!!) }
-            .map {
+            .mapNotNull {
                 assert(it.second!! > 0 && it.second!! < MAX_PORT_NUMBER)
                 report(DaemonReportCategory.DEBUG, "found daemon on port ${it.second}, trying to connect")
                 val daemon = tryConnectToDaemon(it.second!!, report)
@@ -62,7 +62,6 @@ fun walkDaemons(registryDir: File,
                 }
                 daemon
             }
-            .filterNotNull()
 }
 
 
diff --git a/compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt b/compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt
index 92fb161fb06..2cad714e750 100644
--- a/compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt
+++ b/compiler/daemon/src/org/jetbrains/kotlin/daemon/CompileServiceImpl.kt
@@ -142,7 +142,7 @@ class CompileServiceImpl(
 
     override fun getClients(): CompileService.CallResult<List<String>> = ifAlive {
         synchronized(state.clientProxies) {
-            state.clientProxies.map { it.aliveFlagPath }.filterNotNull()
+            state.clientProxies.mapNotNull { it.aliveFlagPath }
         }
     }