diff --git a/classlib/src/main/java/org/teavm/classlib/java/lang/TCharacter.java b/classlib/src/main/java/org/teavm/classlib/java/lang/TCharacter.java
index 488e1c541..122689df5 100644
--- a/classlib/src/main/java/org/teavm/classlib/java/lang/TCharacter.java
+++ b/classlib/src/main/java/org/teavm/classlib/java/lang/TCharacter.java
@@ -242,7 +242,7 @@ public class TCharacter extends TObject implements TComparable<TCharacter> {
         return toLowerCaseSystem(codePoint);
     }
 
-    @Import(module = "runtime", name = "towlower")
+    @Import(module = "runtime", name = "tolower")
     private static native int toLowerCaseSystem(int codePoint);
 
     public static char toUpperCase(char ch) {
@@ -258,7 +258,7 @@ public class TCharacter extends TObject implements TComparable<TCharacter> {
         return toUpperCaseSystem(codePoint);
     }
 
-    @Import(module = "runtime", name = "towupper")
+    @Import(module = "runtime", name = "toupper")
     private static native int toUpperCaseSystem(int codePoint);
 
     public static int digit(char ch, int radix) {
diff --git a/core/src/main/java/org/teavm/backend/wasm/WasmTarget.java b/core/src/main/java/org/teavm/backend/wasm/WasmTarget.java
index 22af8563c..83361c23c 100644
--- a/core/src/main/java/org/teavm/backend/wasm/WasmTarget.java
+++ b/core/src/main/java/org/teavm/backend/wasm/WasmTarget.java
@@ -398,7 +398,7 @@ public class WasmTarget implements TeaVMTarget, TeaVMWasmHost {
     private class IntrinsicFactoryContext implements WasmIntrinsicFactoryContext {
         private ListableClassReaderSource classSource;
 
-        public IntrinsicFactoryContext(ListableClassReaderSource classSource) {
+        IntrinsicFactoryContext(ListableClassReaderSource classSource) {
             this.classSource = classSource;
         }
 
@@ -610,7 +610,7 @@ public class WasmTarget implements TeaVMTarget, TeaVMWasmHost {
         body.add(new WasmReturn(itemTest));
     }
 
-    private WasmFunction generateStub(WasmModule module, MethodHolder method, MethodHolder implementor) {
+    private void generateStub(WasmModule module, MethodHolder method, MethodHolder implementor) {
         WasmFunction function = module.getFunctions().get(WasmMangling.mangleMethod(method.getReference()));
 
         WasmCall call = new WasmCall(WasmMangling.mangleMethod(implementor.getReference()));
@@ -625,7 +625,6 @@ public class WasmTarget implements TeaVMTarget, TeaVMWasmHost {
         } else {
             function.getBody().add(new WasmReturn(call));
         }
-        return function;
     }
 
     private void renderClinit(ListableClassReaderSource classes, WasmClassGenerator classGenerator,
diff --git a/core/src/main/java/org/teavm/backend/wasm/render/WasmBinaryRenderer.java b/core/src/main/java/org/teavm/backend/wasm/render/WasmBinaryRenderer.java
index 2b27f1779..0ef320d54 100644
--- a/core/src/main/java/org/teavm/backend/wasm/render/WasmBinaryRenderer.java
+++ b/core/src/main/java/org/teavm/backend/wasm/render/WasmBinaryRenderer.java
@@ -16,6 +16,7 @@
 package org.teavm.backend.wasm.render;
 
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -47,7 +48,6 @@ public class WasmBinaryRenderer {
     private WasmBinaryVersion version;
     private List<WasmSignature> signatures = new ArrayList<>();
     private Map<WasmSignature, Integer> signatureIndexes = new HashMap<>();
-    private Map<String, Integer> importIndexes = new HashMap<>();
     private Map<String, Integer> functionIndexes = new HashMap<>();
 
     public WasmBinaryRenderer(WasmBinaryWriter output, WasmBinaryVersion version) {
@@ -106,7 +106,6 @@ public class WasmBinaryRenderer {
     }
 
     private void renderImports(WasmModule module) {
-        int index = 0;
         List<WasmFunction> functions = new ArrayList<>();
         for (WasmFunction function : module.getFunctions().values()) {
             if (function.getImportName() == null) {
@@ -332,17 +331,21 @@ public class WasmBinaryRenderer {
     private void renderNames(WasmModule module) {
         WasmBinaryWriter section = new WasmBinaryWriter();
 
-        List<WasmFunction> functions = module.getFunctions().values().stream()
-                .filter(function -> function.getImportName() == null)
-                .collect(Collectors.toList());
+        WasmBinaryWriter functionsSubsection = new WasmBinaryWriter();
+        Collection<WasmFunction> functions = module.getFunctions().values();
 
-        section.writeLEB(functions.size());
+        functionsSubsection.writeLEB(functions.size());
 
         for (WasmFunction function : functions) {
-            section.writeAsciiString(function.getName());
-            section.writeLEB(0);
+            functionsSubsection.writeLEB(functionIndexes.get(function.getName()));
+            functionsSubsection.writeAsciiString(function.getName());
         }
 
+        byte[] payload = functionsSubsection.getData();
+        section.writeLEB(1);
+        section.writeLEB(payload.length);
+        section.writeBytes(payload);
+
         writeSection(SECTION_UNKNOWN, "name", section.getData());
     }
 
@@ -350,7 +353,7 @@ public class WasmBinaryRenderer {
         WasmType type;
         int count = 1;
 
-        public LocalEntry(WasmType type) {
+        LocalEntry(WasmType type) {
             this.type = type;
         }
     }