diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/Exceptions.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/Exceptions.kt
index c88714a65fd..a9decec4b8e 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/Exceptions.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/Exceptions.kt
@@ -20,3 +20,9 @@ package org.jetbrains.kotlin.backend.konan
  * Represents a compilation error caused by mistakes in an input file, e.g. undefined reference.
  */
 class KonanCompilationException(message: String = "", cause: Throwable? = null) : Exception(message, cause) {}
+
+/**
+ * Internal compiler error: could not deserialize IR for inline function body.
+ */
+class KonanIrDeserializationException(message: String = "", cause: Throwable? = null) : Exception(message, cause)
+
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/IrDescriptorDeserializer.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/IrDescriptorDeserializer.kt
index eeea0ba31d7..e93e995bb80 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/IrDescriptorDeserializer.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/IrDescriptorDeserializer.kt
@@ -87,6 +87,7 @@ internal class IrDescriptorDeserializer(val context: Context,
         val text = proto.getDebugText()
         val typeProto = localDeserializer.typeTable[index]
         val type = localDeserializer.deserializeInlineType(typeProto)
+        if (type.isError) throw KonanIrDeserializationException("Could not deserialize KotlinType: $text $type")
         context.log("### deserialized Kotlin Type index=$index, text=$text:\t$type")
 
         return type
@@ -111,7 +112,7 @@ internal class IrDescriptorDeserializer(val context: Context,
             }
             // TODO
             //  proto.hasClazz() -> 
-            else -> error("Unexpected descriptor kind")
+            else -> TODO("Unexpected descriptor kind")
         }
     }
 
@@ -272,7 +273,7 @@ internal class IrDescriptorDeserializer(val context: Context,
                 newPropertyDescriptor.getter
             is PropertySetterDescriptor ->
                 newPropertyDescriptor.setter
-            else -> error("Unexpected accessor kind")
+            else -> TODO("Unexpected accessor kind")
         }
 
         descriptorIndex.put(proto.index, newDescriptor!!)
@@ -312,7 +313,7 @@ internal class IrDescriptorDeserializer(val context: Context,
             is ClassDescriptor -> parent.getUnsubstitutedMemberScope()
             is PackageFragmentDescriptor -> parent.getMemberScope()
             is PackageViewDescriptor -> parent.memberScope
-            else -> error("could not get a member scope")
+            else -> TODO("could not get a member scope")
         }
     }
 
@@ -450,7 +451,7 @@ internal class IrDescriptorDeserializer(val context: Context,
                 // class descriptors here?
                 //substituteClass(proto, originalDescriptor)
                 originalDescriptor
-            else -> error("unexpected type of public function")
+            else -> TODO("unexpected type of public function")
         }
     }
 
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/LocalDeclarationDeserializer.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/LocalDeclarationDeserializer.kt
index 077f792d656..bee84882338 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/LocalDeclarationDeserializer.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/LocalDeclarationDeserializer.kt
@@ -72,7 +72,7 @@ class LocalDeclarationDeserializer(val rootFunction: FunctionDescriptor, val mod
                 return module.findClassAcrossModuleDependencies(nameResolver.getClassId(fqNameIndex))!!
             QualifiedName.Kind.PACKAGE ->
                 return module.getPackage(packageName)
-            else -> error("Unexpected descriptor kind.")
+            else -> TODO("Unexpected descriptor kind.")
         }
     }
 
diff --git a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/SerializeIr.kt b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/SerializeIr.kt
index 59e8913ad26..85f6003dda6 100644
--- a/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/SerializeIr.kt
+++ b/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/serialization/SerializeIr.kt
@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.backend.konan.Context
 import org.jetbrains.kotlin.backend.konan.descriptors.getMemberScope
 import org.jetbrains.kotlin.backend.konan.ir.ir2string
 import org.jetbrains.kotlin.backend.konan.ir.ir2stringWhole
+import org.jetbrains.kotlin.backend.konan.KonanIrDeserializationException
 import org.jetbrains.kotlin.backend.konan.llvm.base64Decode
 import org.jetbrains.kotlin.backend.konan.llvm.base64Encode
 import org.jetbrains.kotlin.descriptors.*
@@ -313,7 +314,7 @@ internal class IrSerializer(val context: Context,
                 -> return KonanIr.IrTypeOperator.INSTANCEOF
             IrTypeOperator.NOT_INSTANCEOF
                 -> return KonanIr.IrTypeOperator.NOT_INSTANCEOF
-            else -> error("Unknown type operator")
+            else -> TODO("Unknown type operator")
         }
     }
 
@@ -689,7 +690,7 @@ internal class IrDeserializer(val context: Context,
                 IrUnaryPrimitiveImpl(start, end, null, descriptor)
             KonanIr.IrCall.Primitive.BINARY ->
                 IrBinaryPrimitiveImpl(start, end, null, descriptor)
-            else -> error("Unexpected primitive IrCall.")
+            else -> TODO("Unexpected primitive IrCall.")
         }
         deserializeMemberAccessCommon(call, proto.memberAccess)
         return call
@@ -802,7 +803,7 @@ internal class IrDeserializer(val context: Context,
                 -> return IrTypeOperator.INSTANCEOF
             KonanIr.IrTypeOperator.NOT_INSTANCEOF
                 -> return IrTypeOperator.NOT_INSTANCEOF
-            else -> error("Unknown type operator")
+            else -> TODO("Unknown type operator")
         }
     }
 
@@ -1037,7 +1038,7 @@ internal class IrDeserializer(val context: Context,
         val proto = (rootFunction as DeserializedSimpleFunctionDescriptor).proto
 
         if (!proto.hasExtension(KonanLinkData.inlineIrBody)) {
-            error("$rootFunction doesn't have ir serialized.")
+            throw KonanIrDeserializationException("$rootFunction doesn't have ir serialized.")
         }
 
         val inlineProto = proto.getExtension(KonanLinkData.inlineIrBody)