diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/PersistentLogicSystem.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/PersistentLogicSystem.kt
index cec3738407f..dca078597ed 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/PersistentLogicSystem.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/PersistentLogicSystem.kt
@@ -161,6 +161,7 @@ abstract class PersistentLogicSystem(context: ConeInferenceContext) : LogicSyste
     }
 
     override fun addTypeStatement(flow: PersistentFlow, statement: TypeStatement) {
+        if (statement.isEmpty) return
         with(flow) {
             approvedTypeStatements = approvedTypeStatements.addTypeStatement(statement)
             if (previousFlow != null) {
@@ -173,6 +174,7 @@ abstract class PersistentLogicSystem(context: ConeInferenceContext) : LogicSyste
     }
 
     override fun addImplication(flow: PersistentFlow, implication: Implication) {
+        if ((implication.effect as? TypeStatement)?.isEmpty == true) return
         if (implication.condition == implication.effect) return
         with(flow) {
             val variable = implication.condition.variable
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/model.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/model.kt
index 9f16780771d..ad3b4c4d918 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/model.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/dfa/model.kt
@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.resolve.dfa.Operation
 import org.jetbrains.kotlin.fir.symbols.AbstractFirBasedSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirCallableSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
+import org.jetbrains.kotlin.fir.types.ConeClassErrorType
 import org.jetbrains.kotlin.fir.types.ConeKotlinType
 
 // --------------------------------------- Variables ---------------------------------------
@@ -207,8 +208,16 @@ infix fun OperationStatement.implies(effect: Statement<*>): Implication = Implic
 
 infix fun RealVariable.typeEq(types: MutableSet<ConeKotlinType>): TypeStatement = MutableTypeStatement(this, types, HashSet())
 infix fun RealVariable.typeEq(type: ConeKotlinType): TypeStatement =
-    MutableTypeStatement(this, HashSet<ConeKotlinType>().apply { this += type }, HashSet())
+    if (type !is ConeClassErrorType) {
+        MutableTypeStatement(this, HashSet<ConeKotlinType>().apply { this += type }, HashSet())
+    } else {
+        MutableTypeStatement(this)
+    }
 
 infix fun RealVariable.typeNotEq(types: MutableSet<ConeKotlinType>): TypeStatement = MutableTypeStatement(this, HashSet(), types)
 infix fun RealVariable.typeNotEq(type: ConeKotlinType): TypeStatement =
-    MutableTypeStatement(this, HashSet(), HashSet<ConeKotlinType>().apply { this += type })
\ No newline at end of file
+    if (type !is ConeClassErrorType) {
+        MutableTypeStatement(this, HashSet(), HashSet<ConeKotlinType>().apply { this += type })
+    } else {
+        MutableTypeStatement(this)
+    }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/arithmetic.fir.kt b/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/arithmetic.fir.kt
index c70fa9c521c..2207ca812c9 100644
--- a/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/arithmetic.fir.kt
+++ b/compiler/testData/diagnostics/tests/platformTypes/nullabilityWarnings/arithmetic.fir.kt
@@ -38,7 +38,7 @@ fun test() {
     1 + platformJ
 
     platformNN + 1
-    platformN + 1
+    platformN <!INAPPLICABLE_CANDIDATE!>+<!> 1
     platformJ + 1
 
     1 plus platformNN
@@ -46,10 +46,10 @@ fun test() {
     1 plus platformJ
 
     platformNN plus 1
-    platformN plus 1
+    platformN <!INAPPLICABLE_CANDIDATE!>plus<!> 1
     platformJ plus 1
 
     platformNN += 1
-    platformN += 1
+    <!UNRESOLVED_REFERENCE!>platformN += 1<!>
     platformJ += 1
 }
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/smartCasts/varnotnull/plusplusMinusminus.fir.kt b/compiler/testData/diagnostics/tests/smartCasts/varnotnull/plusplusMinusminus.fir.kt
index dc2a9386d1f..3715e9d1bfd 100644
--- a/compiler/testData/diagnostics/tests/smartCasts/varnotnull/plusplusMinusminus.fir.kt
+++ b/compiler/testData/diagnostics/tests/smartCasts/varnotnull/plusplusMinusminus.fir.kt
@@ -12,7 +12,7 @@ operator fun Long?.inc() = this?.let { it + 1 }
 fun bar(arg: Long?): Long {
     var i = arg
     if (i++ == 5L) {
-        return i<!INAPPLICABLE_CANDIDATE!>--<!> + i
+        return i<!INAPPLICABLE_CANDIDATE!>--<!> <!INAPPLICABLE_CANDIDATE!>+<!> i
     }
     if (i++ == 7L) {
         return i++ <!INAPPLICABLE_CANDIDATE!>+<!> i