diff --git a/js/js.tests/test/org/jetbrains/kotlin/js/test/JsLineNumberTestGenerated.java b/js/js.tests/test/org/jetbrains/kotlin/js/test/JsLineNumberTestGenerated.java
index 61588b1ae7e..c42eff26d15 100644
--- a/js/js.tests/test/org/jetbrains/kotlin/js/test/JsLineNumberTestGenerated.java
+++ b/js/js.tests/test/org/jetbrains/kotlin/js/test/JsLineNumberTestGenerated.java
@@ -48,6 +48,18 @@ public class JsLineNumberTestGenerated extends AbstractJsLineNumberTest {
         doTest(fileName);
     }
 
+    @TestMetadata("multipleReferences.kt")
+    public void testMultipleReferences() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/lineNumbers/multipleReferences.kt");
+        doTest(fileName);
+    }
+
+    @TestMetadata("optionalArgs.kt")
+    public void testOptionalArgs() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/lineNumbers/optionalArgs.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("simple.kt")
     public void testSimple() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("js/js.translator/testData/lineNumbers/simple.kt");
diff --git a/js/js.translator/src/org/jetbrains/kotlin/js/translate/context/TranslationContext.java b/js/js.translator/src/org/jetbrains/kotlin/js/translate/context/TranslationContext.java
index 8342a7c21d8..facfebe4923 100644
--- a/js/js.translator/src/org/jetbrains/kotlin/js/translate/context/TranslationContext.java
+++ b/js/js.translator/src/org/jetbrains/kotlin/js/translate/context/TranslationContext.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -390,7 +390,8 @@ public class TranslationContext {
             return nameRef;
         }
 
-        return aliasingContext.getAliasForDescriptor(descriptor);
+        JsExpression alias = aliasingContext.getAliasForDescriptor(descriptor);
+        return alias != null ? alias.deepCopy() : null;
     }
 
     @NotNull
diff --git a/js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/FunctionBodyTranslator.java b/js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/FunctionBodyTranslator.java
index 92da07466bc..db89d45b9ef 100644
--- a/js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/FunctionBodyTranslator.java
+++ b/js/js.translator/src/org/jetbrains/kotlin/js/translate/utils/FunctionBodyTranslator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2017 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,6 +32,7 @@ import org.jetbrains.kotlin.js.translate.general.Translation;
 import org.jetbrains.kotlin.js.translate.reference.ReferenceTranslator;
 import org.jetbrains.kotlin.psi.KtDeclarationWithBody;
 import org.jetbrains.kotlin.psi.KtExpression;
+import org.jetbrains.kotlin.resolve.source.KotlinSourceElementKt;
 import org.jetbrains.kotlin.types.KotlinType;
 
 import java.util.ArrayList;
@@ -86,6 +87,7 @@ public final class FunctionBodyTranslator extends AbstractTranslator {
             JsStatement assignStatement = assignment(jsNameRef, defaultValue).makeStmt();
             JsStatement thenStatement = JsAstUtils.mergeStatementInBlockIfNeeded(assignStatement, defaultArgBlock);
             JsBinaryOperation checkArgIsUndefined = equality(jsNameRef, Namer.getUndefinedExpression());
+            checkArgIsUndefined.source(KotlinSourceElementKt.getPsi(valueParameter.getSource()));
             JsIf jsIf = JsAstUtils.newJsIf(checkArgIsUndefined, thenStatement);
             result.add(jsIf);
         }
diff --git a/js/js.translator/testData/lineNumbers/multipleReferences.kt b/js/js.translator/testData/lineNumbers/multipleReferences.kt
new file mode 100644
index 00000000000..d4d72176b26
--- /dev/null
+++ b/js/js.translator/testData/lineNumbers/multipleReferences.kt
@@ -0,0 +1,15 @@
+fun box(x: Int) {
+    println(x)
+    println("split")
+    println(x)
+
+    println(O.y)
+    println("split")
+    println(O.y)
+}
+
+object O {
+    val y = 23
+}
+
+// LINES: 2 3 4 6 7 8 12
diff --git a/js/js.translator/testData/lineNumbers/optionalArgs.kt b/js/js.translator/testData/lineNumbers/optionalArgs.kt
new file mode 100644
index 00000000000..c5e2f72196a
--- /dev/null
+++ b/js/js.translator/testData/lineNumbers/optionalArgs.kt
@@ -0,0 +1,10 @@
+fun box(
+        x: Int = 23,
+        y: Int =
+                 42
+) {
+    println(x)
+    println(y)
+}
+
+// LINES: 2 2 3 4 6 7
\ No newline at end of file