no senseless comparison for error type

compiler/frontend/src/org/jetbrains/jet/lang/types/expressions/BasicExpressionTypingVisitor.java

@@ -1251,6 +1251,8 @@ public class BasicExpressionTypingVisitor extends ExpressionTypingVisitor {
 
         JetSimpleNameExpression operationSign = expression.getOperationReference();
         JetType type = facade.getTypeInfo(expr, context).getType();
+        if (type == null || ErrorUtils.isErrorType(type)) return;
+
         DataFlowValue value = DataFlowValueFactory.INSTANCE.createDataFlowValue(expr, type, context.trace.getBindingContext());
         Nullability nullability = context.dataFlowInfo.getNullability(value);
 

compiler/testData/diagnostics/tests/incompleteCode/NoSenselessComparisonForErrorType.kt

@@ -0,0 +1,8 @@
+package a
+
+fun foo() {
+    val a = <!UNRESOLVED_REFERENCE!>getErrorType<!>()
+    if (<!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>a<!> <!DEBUG_INFO_ELEMENT_WITH_ERROR_TYPE!>==<!> null) { //no senseless comparison
+
+    }
+}

compiler/tests/org/jetbrains/jet/checkers/JetDiagnosticsTestGenerated.java

@@ -1893,6 +1893,11 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
                 doTest("compiler/testData/diagnostics/tests/incompleteCode/kt2014.kt");
             }
             
+            @TestMetadata("NoSenselessComparisonForErrorType.kt")
+            public void testNoSenselessComparisonForErrorType() throws Exception {
+                doTest("compiler/testData/diagnostics/tests/incompleteCode/NoSenselessComparisonForErrorType.kt");
+            }
+            
             @TestMetadata("plusOnTheRight.kt")
             public void testPlusOnTheRight() throws Exception {
                 doTest("compiler/testData/diagnostics/tests/incompleteCode/plusOnTheRight.kt");