diff --git a/compiler/backend/src/org/jetbrains/kotlin/codegen/serialization/JvmSerializerExtension.kt b/compiler/backend/src/org/jetbrains/kotlin/codegen/serialization/JvmSerializerExtension.kt
index dfaa74f9b63..adbfdb7a029 100644
--- a/compiler/backend/src/org/jetbrains/kotlin/codegen/serialization/JvmSerializerExtension.kt
+++ b/compiler/backend/src/org/jetbrains/kotlin/codegen/serialization/JvmSerializerExtension.kt
@@ -301,7 +301,7 @@ class JvmSerializerExtension @JvmOverloads constructor(
         super.serializeErrorType(type, builder)
     }
 
-    private fun <K, V> getBinding(slice: SerializationMappingSlice<K, V>, key: K): V? =
+    private fun <K : Any, V> getBinding(slice: SerializationMappingSlice<K, V>, key: K): V? =
         bindings.get(slice, key) ?: globalBindings.get(slice, key)
 
     private inner class SignatureSerializer {
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ErrorNodeDiagnosticCollectorComponent.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ErrorNodeDiagnosticCollectorComponent.kt
index 94faaaf2074..3128adb18bc 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ErrorNodeDiagnosticCollectorComponent.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/collectors/components/ErrorNodeDiagnosticCollectorComponent.kt
@@ -12,7 +12,9 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirDiagnosticFactory0
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors
 import org.jetbrains.kotlin.fir.declarations.FirErrorFunction
-import org.jetbrains.kotlin.fir.diagnostics.*
+import org.jetbrains.kotlin.fir.diagnostics.ConeDiagnostic
+import org.jetbrains.kotlin.fir.diagnostics.ConeSimpleDiagnostic
+import org.jetbrains.kotlin.fir.diagnostics.ConeStubDiagnostic
 import org.jetbrains.kotlin.fir.diagnostics.DiagnosticKind.*
 import org.jetbrains.kotlin.fir.expressions.FirErrorExpression
 import org.jetbrains.kotlin.fir.expressions.FirErrorLoop
@@ -48,7 +50,7 @@ class ErrorNodeDiagnosticCollectorComponent(collector: AbstractDiagnosticCollect
 
     private fun reportFirDiagnostic(diagnostic: ConeDiagnostic, source: FirSourceElement, reporter: DiagnosticReporter) {
         val coneDiagnostic = when (diagnostic) {
-            is ConeUnresolvedReferenceError -> FirErrors.UNRESOLVED_REFERENCE.on(source, diagnostic.name?.asString())
+            is ConeUnresolvedReferenceError -> FirErrors.UNRESOLVED_REFERENCE.on(source, diagnostic.name?.asString() ?: "<No name>")
             is ConeUnresolvedSymbolError -> FirErrors.UNRESOLVED_REFERENCE.on(source, diagnostic.classId.asString())
             is ConeUnresolvedNameError -> FirErrors.UNRESOLVED_REFERENCE.on(source, diagnostic.name.asString())
             is ConeInapplicableCandidateError -> FirErrors.INAPPLICABLE_CANDIDATE.on(source, diagnostic.candidates.map { it.symbol })
@@ -87,4 +89,4 @@ class ErrorNodeDiagnosticCollectorComponent(collector: AbstractDiagnosticCollect
             else -> throw IllegalArgumentException("Unsupported diagnostic kind: $kind at $javaClass")
         }
     }
-}
\ No newline at end of file
+}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
index 14051374c77..72836096b24 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnostic.kt
@@ -24,18 +24,18 @@ sealed class FirSimpleDiagnostic<out E : FirSourceElement> : FirDiagnostic<E>()
     abstract override val factory: FirDiagnosticFactory0<*, *>
 }
 
-sealed class FirDiagnosticWithParameters1<out E : FirSourceElement, A> : FirDiagnostic<E>() {
+sealed class FirDiagnosticWithParameters1<out E : FirSourceElement, A : Any> : FirDiagnostic<E>() {
     abstract val a: A
     abstract override val factory: FirDiagnosticFactory1<*, *, A>
 }
 
-sealed class FirDiagnosticWithParameters2<out E : FirSourceElement, A, B> : FirDiagnostic<E>() {
+sealed class FirDiagnosticWithParameters2<out E : FirSourceElement, A : Any, B : Any> : FirDiagnostic<E>() {
     abstract val a: A
     abstract val b: B
     abstract override val factory: FirDiagnosticFactory2<*, *, A, B>
 }
 
-sealed class FirDiagnosticWithParameters3<out E : FirSourceElement, A, B, C> : FirDiagnostic<E>() {
+sealed class FirDiagnosticWithParameters3<out E : FirSourceElement, A : Any, B : Any, C : Any> : FirDiagnostic<E>() {
     abstract val a: A
     abstract val b: B
     abstract val c: C
@@ -59,7 +59,7 @@ data class FirPsiSimpleDiagnostic<P : PsiElement>(
     }
 }
 
-data class FirPsiDiagnosticWithParameters1<P : PsiElement, A>(
+data class FirPsiDiagnosticWithParameters1<P : PsiElement, A : Any>(
     override val element: FirPsiSourceElement<P>,
     override val a: A,
     override val severity: Severity,
@@ -70,7 +70,7 @@ data class FirPsiDiagnosticWithParameters1<P : PsiElement, A>(
     }
 }
 
-data class FirPsiDiagnosticWithParameters2<P : PsiElement, A, B>(
+data class FirPsiDiagnosticWithParameters2<P : PsiElement, A : Any, B : Any>(
     override val element: FirPsiSourceElement<P>,
     override val a: A,
     override val b: B,
@@ -82,7 +82,7 @@ data class FirPsiDiagnosticWithParameters2<P : PsiElement, A, B>(
     }
 }
 
-data class FirPsiDiagnosticWithParameters3<P : PsiElement, A, B, C>(
+data class FirPsiDiagnosticWithParameters3<P : PsiElement, A : Any, B : Any, C : Any>(
     override val element: FirPsiSourceElement<P>,
     override val a: A,
     override val b: B,
@@ -107,14 +107,14 @@ data class FirLightSimpleDiagnostic(
     override val factory: FirDiagnosticFactory0<*, *>
 ) : FirSimpleDiagnostic<FirLightSourceElement>(), FirLightDiagnostic
 
-data class FirLightDiagnosticWithParameters1<A>(
+data class FirLightDiagnosticWithParameters1<A : Any>(
     override val element: FirLightSourceElement,
     override val a: A,
     override val severity: Severity,
     override val factory: FirDiagnosticFactory1<*, *, A>
 ) : FirDiagnosticWithParameters1<FirLightSourceElement, A>(), FirLightDiagnostic
 
-data class FirLightDiagnosticWithParameters2<A, B>(
+data class FirLightDiagnosticWithParameters2<A : Any, B : Any>(
     override val element: FirLightSourceElement,
     override val a: A,
     override val b: B,
@@ -122,11 +122,11 @@ data class FirLightDiagnosticWithParameters2<A, B>(
     override val factory: FirDiagnosticFactory2<*, *, A, B>
 ) : FirDiagnosticWithParameters2<FirLightSourceElement, A, B>(), FirLightDiagnostic
 
-data class FirLightDiagnosticWithParameters3<A, B, C>(
+data class FirLightDiagnosticWithParameters3<A : Any, B : Any, C : Any>(
     override val element: FirLightSourceElement,
     override val a: A,
     override val b: B,
     override val c: C,
     override val severity: Severity,
     override val factory: FirDiagnosticFactory3<*, *, A, B, C>
-) : FirDiagnosticWithParameters3<FirLightSourceElement, A, B, C>(), FirLightDiagnostic
\ No newline at end of file
+) : FirDiagnosticWithParameters3<FirLightSourceElement, A, B, C>(), FirLightDiagnostic
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
index abc5c668b18..7e83053a7e7 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactory.kt
@@ -36,7 +36,7 @@ class FirDiagnosticFactory0<E : FirSourceElement, P : PsiElement>(
     }
 }
 
-class FirDiagnosticFactory1<E : FirSourceElement, P : PsiElement, A>(
+class FirDiagnosticFactory1<E : FirSourceElement, P : PsiElement, A : Any>(
     name: String, severity: Severity, override val psiDiagnosticFactory: DiagnosticFactory1<P, A>
 ) : AbstractFirDiagnosticFactory<E, FirDiagnosticWithParameters1<E, A>>(name, severity) {
     fun on(element: E, a: A): FirDiagnosticWithParameters1<E, A> {
@@ -50,7 +50,7 @@ class FirDiagnosticFactory1<E : FirSourceElement, P : PsiElement, A>(
     }
 }
 
-class FirDiagnosticFactory2<E : FirSourceElement, P : PsiElement, A, B>(
+class FirDiagnosticFactory2<E : FirSourceElement, P : PsiElement, A : Any, B : Any>(
     name: String, severity: Severity, override val psiDiagnosticFactory: DiagnosticFactory2<P, A, B>
 ) : AbstractFirDiagnosticFactory<E, FirDiagnosticWithParameters2<E, A, B>>(name, severity) {
     fun on(element: E, a: A, b: B): FirDiagnosticWithParameters2<E, A, B> {
@@ -64,7 +64,7 @@ class FirDiagnosticFactory2<E : FirSourceElement, P : PsiElement, A, B>(
     }
 }
 
-class FirDiagnosticFactory3<E : FirSourceElement, P : PsiElement, A, B, C>(
+class FirDiagnosticFactory3<E : FirSourceElement, P : PsiElement, A : Any, B : Any, C : Any>(
     name: String, severity: Severity, override val psiDiagnosticFactory: DiagnosticFactory3<P, A, B, C>
 ) : AbstractFirDiagnosticFactory<E, FirDiagnosticWithParameters3<E, A, B, C>>(name, severity) {
     fun on(element: E, a: A, b: B, c: C): FirDiagnosticWithParameters3<E, A, B, C> {
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryDsl.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryDsl.kt
index 043169a6482..9188355e41c 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryDsl.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryDsl.kt
@@ -15,15 +15,15 @@ fun <E : FirSourceElement, P : PsiElement> warning0(): DiagnosticFactory0Delegat
     return DiagnosticFactory0DelegateProvider(Severity.WARNING, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A> warning1(): DiagnosticFactory1DelegateProvider<E, P, A> {
+fun <E : FirSourceElement, P : PsiElement, A : Any> warning1(): DiagnosticFactory1DelegateProvider<E, P, A> {
     return DiagnosticFactory1DelegateProvider(Severity.WARNING, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B> warning2(): DiagnosticFactory2DelegateProvider<E, P, A, B> {
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any> warning2(): DiagnosticFactory2DelegateProvider<E, P, A, B> {
     return DiagnosticFactory2DelegateProvider(Severity.WARNING, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B, C> warning3(): DiagnosticFactory3DelegateProvider<E, P, A, B, C> {
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any, C : Any> warning3(): DiagnosticFactory3DelegateProvider<E, P, A, B, C> {
     return DiagnosticFactory3DelegateProvider(Severity.WARNING, null)
 }
 
@@ -31,15 +31,15 @@ fun <E : FirSourceElement, P : PsiElement> error0(): DiagnosticFactory0DelegateP
     return DiagnosticFactory0DelegateProvider(Severity.ERROR, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A> error1(): DiagnosticFactory1DelegateProvider<E, P, A> {
+fun <E : FirSourceElement, P : PsiElement, A : Any> error1(): DiagnosticFactory1DelegateProvider<E, P, A> {
     return DiagnosticFactory1DelegateProvider(Severity.ERROR, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B> error2(): DiagnosticFactory2DelegateProvider<E, P, A, B> {
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any> error2(): DiagnosticFactory2DelegateProvider<E, P, A, B> {
     return DiagnosticFactory2DelegateProvider(Severity.ERROR, null)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B, C> error3(): DiagnosticFactory3DelegateProvider<E, P, A, B, C> {
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any, C : Any> error3(): DiagnosticFactory3DelegateProvider<E, P, A, B, C> {
     return DiagnosticFactory3DelegateProvider(Severity.ERROR, null)
 }
 
@@ -53,19 +53,19 @@ fun <E : FirSourceElement, P : PsiElement> existing(
     return DiagnosticFactory0DelegateProvider(Severity.ERROR, psiDiagnosticFactory)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A> existing(
+fun <E : FirSourceElement, P : PsiElement, A : Any> existing(
     psiDiagnosticFactory: DiagnosticFactory1<P, A>
 ): DiagnosticFactory1DelegateProvider<E, P, A> {
     return DiagnosticFactory1DelegateProvider(Severity.ERROR, psiDiagnosticFactory)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B> existing(
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any> existing(
     psiDiagnosticFactory: DiagnosticFactory2<P, A, B>
 ): DiagnosticFactory2DelegateProvider<E, P, A, B> {
     return DiagnosticFactory2DelegateProvider(Severity.ERROR, psiDiagnosticFactory)
 }
 
-fun <E : FirSourceElement, P : PsiElement, A, B, C> existing(
+fun <E : FirSourceElement, P : PsiElement, A : Any, B : Any, C : Any> existing(
     psiDiagnosticFactory: DiagnosticFactory3<P, A, B, C>
 ): DiagnosticFactory3DelegateProvider<E, P, A, B, C> {
     return DiagnosticFactory3DelegateProvider(Severity.ERROR, psiDiagnosticFactory)
@@ -85,7 +85,7 @@ class DiagnosticFactory0DelegateProvider<E : FirSourceElement, P : PsiElement>(
     }
 }
 
-class DiagnosticFactory1DelegateProvider<E : FirSourceElement, P : PsiElement, A>(
+class DiagnosticFactory1DelegateProvider<E : FirSourceElement, P : PsiElement, A : Any>(
     private val severity: Severity,
     private val psiDiagnosticFactory: DiagnosticFactory1<P, A>?
 ) {
@@ -97,7 +97,7 @@ class DiagnosticFactory1DelegateProvider<E : FirSourceElement, P : PsiElement, A
     }
 }
 
-class DiagnosticFactory2DelegateProvider<E : FirSourceElement, P : PsiElement, A, B>(
+class DiagnosticFactory2DelegateProvider<E : FirSourceElement, P : PsiElement, A : Any, B : Any>(
     private val severity: Severity,
     private val psiDiagnosticFactory: DiagnosticFactory2<P, A, B>?
 ) {
@@ -109,7 +109,7 @@ class DiagnosticFactory2DelegateProvider<E : FirSourceElement, P : PsiElement, A
     }
 }
 
-class DiagnosticFactory3DelegateProvider<E : FirSourceElement, P : PsiElement, A, B, C>(
+class DiagnosticFactory3DelegateProvider<E : FirSourceElement, P : PsiElement, A : Any, B : Any, C : Any>(
     private val severity: Severity,
     private val psiDiagnosticFactory: DiagnosticFactory3<P, A, B, C>?
 ) {
@@ -125,4 +125,4 @@ private class DummyDelegate<T>(val value: T) : ReadOnlyProperty<Any?, T> {
     override fun getValue(thisRef: Any?, property: KProperty<*>): T {
         return value
     }
-}
\ No newline at end of file
+}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
index 74909add2e5..cb7174fb01b 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirDiagnosticFactoryToRendererMap.kt
@@ -21,7 +21,7 @@ class FirDiagnosticFactoryToRendererMap(val name: String) {
         putToFirMap(factory)
     }
 
-    fun <A> put(
+    fun <A : Any> put(
         factory: FirDiagnosticFactory1<*, *, A>,
         message: String,
         rendererA: DiagnosticParameterRenderer<A>?
@@ -30,7 +30,7 @@ class FirDiagnosticFactoryToRendererMap(val name: String) {
         putToFirMap(factory)
     }
 
-    fun <A, B> put(
+    fun <A : Any, B : Any> put(
         factory: FirDiagnosticFactory2<*, *, A, B>,
         message: String,
         rendererA: DiagnosticParameterRenderer<A>?,
@@ -40,7 +40,7 @@ class FirDiagnosticFactoryToRendererMap(val name: String) {
         putToFirMap(factory)
     }
 
-    fun <A, B, C> put(
+    fun <A : Any, B : Any, C : Any> put(
         factory: FirDiagnosticFactory3<*, *, A, B, C>,
         message: String,
         rendererA: DiagnosticParameterRenderer<A>?,
@@ -56,4 +56,4 @@ class FirDiagnosticFactoryToRendererMap(val name: String) {
             diagnosticsMap[factory] = it
         }
     }
-}
\ No newline at end of file
+}
diff --git a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
index 3e01665b474..bd555b00c56 100644
--- a/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
+++ b/compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/diagnostics/FirErrors.kt
@@ -18,7 +18,7 @@ import org.jetbrains.kotlin.lexer.KtModifierKeywordToken
 import org.jetbrains.kotlin.psi.*
 
 object FirErrors {
-    val UNRESOLVED_REFERENCE by error1<FirSourceElement, PsiElement, String?>()
+    val UNRESOLVED_REFERENCE by error1<FirSourceElement, PsiElement, String>()
     val INAPPLICABLE_CANDIDATE by error1<FirSourceElement, PsiElement, Collection<AbstractFirBasedSymbol<*>>>()
     val AMBIGUITY by error1<FirSourceElement, PsiElement, Collection<AbstractFirBasedSymbol<*>>>()
     val ASSIGN_OPERATOR_AMBIGUITY by error1<FirSourceElement, PsiElement, Collection<AbstractFirBasedSymbol<*>>>()
diff --git a/compiler/fir/fir2ir/jvm-backend/src/org/jetbrains/kotlin/fir/backend/jvm/FirJvmSerializerExtension.kt b/compiler/fir/fir2ir/jvm-backend/src/org/jetbrains/kotlin/fir/backend/jvm/FirJvmSerializerExtension.kt
index e5725ee9a33..76e45a90d8e 100644
--- a/compiler/fir/fir2ir/jvm-backend/src/org/jetbrains/kotlin/fir/backend/jvm/FirJvmSerializerExtension.kt
+++ b/compiler/fir/fir2ir/jvm-backend/src/org/jetbrains/kotlin/fir/backend/jvm/FirJvmSerializerExtension.kt
@@ -310,7 +310,7 @@ class FirJvmSerializerExtension @JvmOverloads constructor(
         super.serializeErrorType(type, builder)
     }
 
-    private fun <K, V> getBinding(slice: JvmSerializationBindings.SerializationMappingSlice<K, V>, key: K): V? =
+    private fun <K : Any, V : Any> getBinding(slice: JvmSerializationBindings.SerializationMappingSlice<K, V>, key: K): V? =
         bindings.get(slice, key) ?: globalBindings.get(slice, key)
 
     private inner class SignatureSerializer {
diff --git a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/PsiErrorBuilder.kt b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/PsiErrorBuilder.kt
index 8a0c26df85f..ff82b4c6956 100644
--- a/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/PsiErrorBuilder.kt
+++ b/compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/PsiErrorBuilder.kt
@@ -62,16 +62,16 @@ class PsiErrorBuilder(
             diagnosticSink.report(diagnosticFactory.on(psiElement))
         }
 
-        fun <A> report(diagnosticFactory: DiagnosticFactory1<E, A>, a: A) {
+        fun <A : Any> report(diagnosticFactory: DiagnosticFactory1<E, A>, a: A) {
             diagnosticSink.report(diagnosticFactory.on(psiElement, a))
         }
 
-        fun <A, B> report(diagnosticFactory: DiagnosticFactory2<E, A, B>, a: A, b: B) {
+        fun <A : Any, B : Any> report(diagnosticFactory: DiagnosticFactory2<E, A, B>, a: A, b: B) {
             diagnosticSink.report(diagnosticFactory.on(psiElement, a, b))
         }
 
-        fun <A, B, C> report(diagnosticFactory: DiagnosticFactory3<E, A, B, C>, a: A, b: B, c: C) {
+        fun <A : Any, B : Any, C : Any> report(diagnosticFactory: DiagnosticFactory3<E, A, B, C>, a: A, b: B, c: C) {
             diagnosticSink.report(diagnosticFactory.on(psiElement, a, b, c))
         }
     }
-}
\ No newline at end of file
+}