diff --git a/core/src/main/java/org/teavm/backend/wasm/WasmGCTarget.java b/core/src/main/java/org/teavm/backend/wasm/WasmGCTarget.java
index e8e54d178..4c2ce9111 100644
--- a/core/src/main/java/org/teavm/backend/wasm/WasmGCTarget.java
+++ b/core/src/main/java/org/teavm/backend/wasm/WasmGCTarget.java
@@ -74,6 +74,8 @@ import org.teavm.model.ListableClassHolderSource;
 import org.teavm.model.MethodReader;
 import org.teavm.model.MethodReference;
 import org.teavm.model.Program;
+import org.teavm.model.lowlevel.Characteristics;
+import org.teavm.model.lowlevel.LowLevelNullCheckFilter;
 import org.teavm.model.transformation.BoundCheckInsertion;
 import org.teavm.model.transformation.NullCheckFilter;
 import org.teavm.model.transformation.NullCheckInsertion;
@@ -86,7 +88,8 @@ import org.teavm.vm.spi.TeaVMHostExtension;
 
 public class WasmGCTarget implements TeaVMTarget, TeaVMWasmGCHost {
     private TeaVMTargetController controller;
-    private NullCheckInsertion nullCheckInsertion = new NullCheckInsertion(NullCheckFilter.EMPTY);
+    private Characteristics characteristics;
+    private NullCheckInsertion nullCheckInsertion;
     private BoundCheckInsertion boundCheckInsertion = new BoundCheckInsertion();
     private boolean strict;
     private boolean obfuscated;
@@ -179,6 +182,8 @@ public class WasmGCTarget implements TeaVMTarget, TeaVMWasmGCHost {
     @Override
     public void setController(TeaVMTargetController controller) {
         this.controller = controller;
+        characteristics = new Characteristics(controller.getUnprocessedClassSource());
+        nullCheckInsertion = new NullCheckInsertion(new LowLevelNullCheckFilter(characteristics));
     }
 
     @Override
@@ -267,6 +272,7 @@ public class WasmGCTarget implements TeaVMTarget, TeaVMWasmGCHost {
                 controller.getClassInitializerInfo(),
                 controller.getDependencyInfo(),
                 controller.getDiagnostics(),
+                characteristics,
                 customGenerators,
                 intrinsics,
                 customTypeMapperFactories,
diff --git a/core/src/main/java/org/teavm/backend/wasm/generate/gc/WasmGCDeclarationsGenerator.java b/core/src/main/java/org/teavm/backend/wasm/generate/gc/WasmGCDeclarationsGenerator.java
index ca82f55f1..aa8e64428 100644
--- a/core/src/main/java/org/teavm/backend/wasm/generate/gc/WasmGCDeclarationsGenerator.java
+++ b/core/src/main/java/org/teavm/backend/wasm/generate/gc/WasmGCDeclarationsGenerator.java
@@ -44,6 +44,7 @@ import org.teavm.model.analysis.ClassInitializerInfo;
 import org.teavm.model.analysis.ClassMetadataRequirements;
 import org.teavm.model.classes.TagRegistry;
 import org.teavm.model.classes.VirtualTableBuilder;
+import org.teavm.model.lowlevel.Characteristics;
 
 public class WasmGCDeclarationsGenerator {
     public final ClassHierarchy hierarchy;
@@ -61,6 +62,7 @@ public class WasmGCDeclarationsGenerator {
             ClassInitializerInfo classInitializerInfo,
             DependencyInfo dependencyInfo,
             Diagnostics diagnostics,
+            Characteristics characteristics,
             WasmGCCustomGeneratorProvider customGenerators,
             WasmGCIntrinsicProvider intrinsics,
             List<WasmGCCustomTypeMapperFactory> customTypeMapperFactories,
@@ -83,6 +85,7 @@ public class WasmGCDeclarationsGenerator {
                 functionTypes,
                 names,
                 diagnostics,
+                characteristics,
                 customGenerators,
                 intrinsics,
                 strict,
diff --git a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationContext.java b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationContext.java
index 2a1c9395d..f3c5fa23e 100644
--- a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationContext.java
+++ b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationContext.java
@@ -43,6 +43,7 @@ import org.teavm.model.ClassReaderSource;
 import org.teavm.model.ElementModifier;
 import org.teavm.model.ListableClassReaderSource;
 import org.teavm.model.MethodReference;
+import org.teavm.model.lowlevel.Characteristics;
 
 public class WasmGCGenerationContext implements BaseWasmGenerationContext {
     private WasmModule module;
@@ -69,6 +70,7 @@ public class WasmGCGenerationContext implements BaseWasmGenerationContext {
     private String entryPoint;
     private Consumer<WasmGCInitializerContributor> initializerContributors;
     private Diagnostics diagnostics;
+    private Characteristics characteristics;
 
     public WasmGCGenerationContext(WasmModule module, WasmGCVirtualTableProvider virtualTables,
             WasmGCTypeMapper typeMapper, WasmFunctionTypes functionTypes, ListableClassReaderSource classes,
@@ -78,7 +80,7 @@ public class WasmGCGenerationContext implements BaseWasmGenerationContext {
             WasmGCCustomGeneratorProvider customGenerators, WasmGCIntrinsicProvider intrinsics,
             WasmGCNameProvider names, boolean strict, String entryPoint,
             Consumer<WasmGCInitializerContributor> initializerContributors,
-            Diagnostics diagnostics) {
+            Diagnostics diagnostics, Characteristics characteristics) {
         this.module = module;
         this.virtualTables = virtualTables;
         this.typeMapper = typeMapper;
@@ -98,6 +100,7 @@ public class WasmGCGenerationContext implements BaseWasmGenerationContext {
         this.entryPoint = entryPoint;
         this.initializerContributors = initializerContributors;
         this.diagnostics = diagnostics;
+        this.characteristics = characteristics;
     }
 
     public WasmGCClassInfoProvider classInfoProvider() {
@@ -210,6 +213,10 @@ public class WasmGCGenerationContext implements BaseWasmGenerationContext {
         return diagnostics;
     }
 
+    public Characteristics characteristics() {
+        return characteristics;
+    }
+
     public Collection<String> getInterfaceImplementors(String className) {
         if (interfaceImplementors == null) {
             fillInterfaceImplementors();
diff --git a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java
index 64457d4e3..1bd528b1c 100644
--- a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java
+++ b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCGenerationVisitor.java
@@ -15,6 +15,8 @@
  */
 package org.teavm.backend.wasm.generate.gc.methods;
 
+import static org.teavm.model.lowlevel.ExceptionHandlingUtil.isManagedMethodCall;
+
 import java.util.ArrayList;
 import java.util.List;
 import java.util.function.Consumer;
@@ -97,6 +99,7 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
     private WasmGCGenerationUtil generationUtil;
     private WasmType expectedType;
     private PreciseTypeInference types;
+    private boolean managed;
 
     public WasmGCGenerationVisitor(WasmGCGenerationContext context, MethodReference currentMethod,
             WasmFunction function, int firstVariable, boolean async, PreciseTypeInference types) {
@@ -104,6 +107,7 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
         this.context = context;
         generationUtil = new WasmGCGenerationUtil(context.classInfoProvider());
         this.types = types;
+        managed = context.characteristics().isManaged(currentMethod);
     }
 
     @Override
@@ -125,7 +129,7 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
 
     @Override
     protected boolean isManaged() {
-        return true;
+        return managed;
     }
 
     @Override
@@ -135,7 +139,7 @@ public class WasmGCGenerationVisitor extends BaseWasmGenerationVisitor {
 
     @Override
     protected boolean isManagedCall(MethodReference method) {
-        return false;
+        return isManagedMethodCall(context.characteristics(), method);
     }
 
     @Override
diff --git a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCMethodGenerator.java b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCMethodGenerator.java
index 6365d7cd1..2d946ad32 100644
--- a/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCMethodGenerator.java
+++ b/core/src/main/java/org/teavm/backend/wasm/generate/gc/methods/WasmGCMethodGenerator.java
@@ -61,6 +61,7 @@ import org.teavm.model.MethodReader;
 import org.teavm.model.MethodReference;
 import org.teavm.model.ValueType;
 import org.teavm.model.analysis.ClassInitializerInfo;
+import org.teavm.model.lowlevel.Characteristics;
 import org.teavm.model.util.RegisterAllocator;
 
 public class WasmGCMethodGenerator implements BaseWasmFunctionRepository {
@@ -74,6 +75,7 @@ public class WasmGCMethodGenerator implements BaseWasmFunctionRepository {
     private WasmGCSupertypeFunctionProvider supertypeFunctions;
     public final WasmGCNameProvider names;
     private Diagnostics diagnostics;
+    private Characteristics characteristics;
     private WasmGCTypeMapper typeMapper;
     private WasmGCCustomGeneratorProvider customGenerators;
     private WasmGCIntrinsicProvider intrinsics;
@@ -101,6 +103,7 @@ public class WasmGCMethodGenerator implements BaseWasmFunctionRepository {
             WasmFunctionTypes functionTypes,
             WasmGCNameProvider names,
             Diagnostics diagnostics,
+            Characteristics characteristics,
             WasmGCCustomGeneratorProvider customGenerators,
             WasmGCIntrinsicProvider intrinsics,
             boolean strict,
@@ -116,6 +119,7 @@ public class WasmGCMethodGenerator implements BaseWasmFunctionRepository {
         this.functionTypes = functionTypes;
         this.names = names;
         this.diagnostics = diagnostics;
+        this.characteristics = characteristics;
         this.customGenerators = customGenerators;
         this.intrinsics = intrinsics;
         this.strict = strict;
@@ -367,7 +371,8 @@ public class WasmGCMethodGenerator implements BaseWasmFunctionRepository {
                     strict,
                     entryPoint,
                     initializerContributors,
-                    diagnostics
+                    diagnostics,
+                    characteristics
             );
         }
         return context;