diff --git a/compiler/frontend/src/org/jetbrains/kotlin/cfg/JetControlFlowProcessor.java b/compiler/frontend/src/org/jetbrains/kotlin/cfg/JetControlFlowProcessor.java
index f7d478e6a3b..8d34e1869e0 100644
--- a/compiler/frontend/src/org/jetbrains/kotlin/cfg/JetControlFlowProcessor.java
+++ b/compiler/frontend/src/org/jetbrains/kotlin/cfg/JetControlFlowProcessor.java
@@ -585,7 +585,15 @@ public class JetControlFlowProcessor {
                 accessTarget = getDeclarationAccessTarget(left);
             }
 
-            recordWrite(left, accessTarget, rhsDeferredValue.invoke(), receiverValues, parentExpression);
+            if (accessTarget == AccessTarget.BlackBox.INSTANCE$ && !(left instanceof JetProperty)) {
+                generateInstructions(left);
+                createSyntheticValue(left, MagicKind.VALUE_CONSUMER, left);
+            }
+
+            PseudoValue rightValue = rhsDeferredValue.invoke();
+            PseudoValue rValue =
+                    rightValue != null ? rightValue : createSyntheticValue(parentExpression, MagicKind.UNRECOGNIZED_WRITE_RHS);
+            builder.write(parentExpression, left, rValue, accessTarget, receiverValues);
         }
 
         private void generateArrayAssignment(
@@ -663,24 +671,6 @@ public class JetControlFlowProcessor {
             return argumentValues;
         }
 
-        private void recordWrite(
-                @NotNull JetExpression left,
-                @NotNull AccessTarget target,
-                @Nullable PseudoValue rightValue,
-                @NotNull Map<PseudoValue, ReceiverValue> receiverValues,
-                @NotNull JetExpression parentExpression
-        ) {
-            if (target == AccessTarget.BlackBox.INSTANCE$) {
-                List<PseudoValue> values = ContainerUtil.createMaybeSingletonList(rightValue);
-                builder.magic(parentExpression, parentExpression, values, defaultTypeMap(values), MagicKind.UNSUPPORTED_ELEMENT);
-            }
-            else {
-                PseudoValue rValue =
-                        rightValue != null ? rightValue : createSyntheticValue(parentExpression, MagicKind.UNRECOGNIZED_WRITE_RHS);
-                builder.write(parentExpression, left, rValue, target, receiverValues);
-            }
-        }
-
         private void generateArrayAccess(JetArrayAccessExpression arrayAccessExpression, @Nullable ResolvedCall<?> resolvedCall) {
             if (builder.getBoundValue(arrayAccessExpression) != null) return;
             mark(arrayAccessExpression);
diff --git a/compiler/testData/cfg/expressions/assignmentToThis.instructions b/compiler/testData/cfg/expressions/assignmentToThis.instructions
index 1252b97f023..c060be35c16 100644
--- a/compiler/testData/cfg/expressions/assignmentToThis.instructions
+++ b/compiler/testData/cfg/expressions/assignmentToThis.instructions
@@ -9,12 +9,14 @@ L0:
     magic[FAKE_INITIALIZER](c: C) -> <v0>
     w(c|<v0>)
   2 mark({ this = c })
-    r(c) -> <v1>
-    magic[UNSUPPORTED_ELEMENT](this = c|<v1>) -> <v2>
+    r(this, <this>) -> <v1>
+    magic[VALUE_CONSUMER](this|<v1>) -> <v2>
+    r(c) -> <v3>
+    w(this|<v3>)
 L1:
-  1 <END>                                                NEXT:[<SINK>]
+  1 <END>                                       NEXT:[<SINK>]
 error:
-    <ERROR>                                              PREV:[]
+    <ERROR>                                     PREV:[]
 sink:
-    <SINK>                                               PREV:[<ERROR>, <END>]
-=====================
\ No newline at end of file
+    <SINK>                                      PREV:[<ERROR>, <END>]
+=====================
diff --git a/compiler/testData/cfg/expressions/assignmentToThis.values b/compiler/testData/cfg/expressions/assignmentToThis.values
index 3121c81908d..491d3789f6e 100644
--- a/compiler/testData/cfg/expressions/assignmentToThis.values
+++ b/compiler/testData/cfg/expressions/assignmentToThis.values
@@ -4,7 +4,10 @@ fun Int.bar(c: C) {
 }
 ---------------------
                <v0>: {<: [ERROR : C]}   NEW: magic[FAKE_INITIALIZER](c: C) -> <v0>
-c              <v1>: *                  NEW: r(c) -> <v1>
-this = c       <v2>: *                  NEW: magic[UNSUPPORTED_ELEMENT](this = c|<v1>) -> <v2>
-{ this = c }   <v2>: *                  COPY
+               <v2>: *                  NEW: magic[VALUE_CONSUMER](this|<v1>) -> <v2>
+this           <v1>: *                  COPY
+this           <v1>: *                  NEW: r(this, <this>) -> <v1>
+c              <v3>: *                  NEW: r(c) -> <v3>
+this = c       !<v4>: *
+{ this = c }   !<v4>: *                 COPY
 =====================
diff --git a/compiler/testData/cfg/expressions/unresolvedWriteLHS.instructions b/compiler/testData/cfg/expressions/unresolvedWriteLHS.instructions
index 7a929be8f3f..c5b37f7f1ff 100644
--- a/compiler/testData/cfg/expressions/unresolvedWriteLHS.instructions
+++ b/compiler/testData/cfg/expressions/unresolvedWriteLHS.instructions
@@ -6,13 +6,15 @@ fun foo() {
 L0:
   1 <START>
   2 mark({ x = "" })
+    magic[UNRESOLVED_CALL](x) -> <v0>
+    magic[VALUE_CONSUMER](x|<v0>) -> <v1>
     mark("")
-    r("") -> <v0>
-    magic[UNSUPPORTED_ELEMENT](x = ""|<v0>) -> <v1>
+    r("") -> <v2>
+    w(x|<v2>)
 L1:
-  1 <END>                                              NEXT:[<SINK>]
+  1 <END>                                    NEXT:[<SINK>]
 error:
-    <ERROR>                                            PREV:[]
+    <ERROR>                                  PREV:[]
 sink:
-    <SINK>                                             PREV:[<ERROR>, <END>]
-=====================
\ No newline at end of file
+    <SINK>                                   PREV:[<ERROR>, <END>]
+=====================
diff --git a/compiler/testData/cfg/expressions/unresolvedWriteLHS.values b/compiler/testData/cfg/expressions/unresolvedWriteLHS.values
index 70ca650ecb8..a2c04e03388 100644
--- a/compiler/testData/cfg/expressions/unresolvedWriteLHS.values
+++ b/compiler/testData/cfg/expressions/unresolvedWriteLHS.values
@@ -3,7 +3,9 @@ fun foo() {
     x = ""
 }
 ---------------------
-""           <v0>: *   NEW: r("") -> <v0>
-x = ""       <v1>: *   NEW: magic[UNSUPPORTED_ELEMENT](x = ""|<v0>) -> <v1>
-{ x = "" }   <v1>: *   COPY
+             <v1>: *    NEW: magic[VALUE_CONSUMER](x|<v0>) -> <v1>
+x            <v0>: *    NEW: magic[UNRESOLVED_CALL](x) -> <v0>
+""           <v2>: *    NEW: r("") -> <v2>
+x = ""       !<v3>: *
+{ x = "" }   !<v3>: *   COPY
 =====================
diff --git a/compiler/testData/diagnostics/tests/LValueAssignment.kt b/compiler/testData/diagnostics/tests/LValueAssignment.kt
index 3cdb597d207..ded49c502fc 100644
--- a/compiler/testData/diagnostics/tests/LValueAssignment.kt
+++ b/compiler/testData/diagnostics/tests/LValueAssignment.kt
@@ -39,7 +39,7 @@ class D() {
 fun foo(): Unit {}
 
 fun cannotBe() {
-    var <!UNUSED_VARIABLE!>i<!>: Int = 5
+    var i: Int = 5
 
     <!UNRESOLVED_REFERENCE!>z<!> = 30;
     <!VARIABLE_EXPECTED!>""<!> = "";
@@ -135,4 +135,4 @@ fun Array<Int>.checkThis() {
 
 abstract class Ab {
     abstract fun getArray() : Array<Int>
-}
+}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/UnusedParameters.kt b/compiler/testData/diagnostics/tests/UnusedParameters.kt
index a160285e259..17e344f27d5 100644
--- a/compiler/testData/diagnostics/tests/UnusedParameters.kt
+++ b/compiler/testData/diagnostics/tests/UnusedParameters.kt
@@ -26,3 +26,7 @@ fun get(p: Any) {
 
 fun set(p: Any) {
 }
+
+fun foo(s: String) {
+    s.<!UNRESOLVED_REFERENCE!>xxx<!> = 1
+}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/UnusedParameters.txt b/compiler/testData/diagnostics/tests/UnusedParameters.txt
index d52fc07037f..9ce670bf8e4 100644
--- a/compiler/testData/diagnostics/tests/UnusedParameters.txt
+++ b/compiler/testData/diagnostics/tests/UnusedParameters.txt
@@ -1,6 +1,7 @@
 package
 
 internal fun f(/*0*/ a: kotlin.Int, /*1*/ b: kotlin.Int, /*2*/ c: kotlin.Int = ...): kotlin.Unit
+internal fun foo(/*0*/ s: kotlin.String): kotlin.Unit
 internal fun get(/*0*/ p: kotlin.Any): kotlin.Unit
 internal fun set(/*0*/ p: kotlin.Any): kotlin.Unit
 internal fun kotlin.Any.get(/*0*/ thisRef: kotlin.Any?, /*1*/ prop: kotlin.PropertyMetadata): kotlin.String