diff --git a/plugins/kotlinx-serialization/kotlinx-serialization.k2/src/org/jetbrains/kotlinx/serialization/compiler/fir/checkers/FirSerializationPluginClassChecker.kt b/plugins/kotlinx-serialization/kotlinx-serialization.k2/src/org/jetbrains/kotlinx/serialization/compiler/fir/checkers/FirSerializationPluginClassChecker.kt
index 093c5eef118..86a9cdb1d2e 100644
--- a/plugins/kotlinx-serialization/kotlinx-serialization.k2/src/org/jetbrains/kotlinx/serialization/compiler/fir/checkers/FirSerializationPluginClassChecker.kt
+++ b/plugins/kotlinx-serialization/kotlinx-serialization.k2/src/org/jetbrains/kotlinx/serialization/compiler/fir/checkers/FirSerializationPluginClassChecker.kt
@@ -248,7 +248,9 @@ object FirSerializationPluginClassChecker : FirClassChecker() {
         }
 
         if (with(session) { classSymbol.serializableAnnotationIsUseless }) {
-            reporter.reportOn(classSymbol.serializableOrMetaAnnotationSource, FirSerializationErrors.SERIALIZABLE_ANNOTATION_IGNORED)
+            classSymbol.serializableOrMetaAnnotationSource?.let {
+                reporter.reportOn(it, FirSerializationErrors.SERIALIZABLE_ANNOTATION_IGNORED)
+            }
             return false
         }