diff --git a/core/src/main/java/org/jruby/ir/instructions/ProcessModuleBodyInstr.java b/core/src/main/java/org/jruby/ir/instructions/ProcessModuleBodyInstr.java
index 75ebd71da08..ea4d53febb0 100644
--- a/core/src/main/java/org/jruby/ir/instructions/ProcessModuleBodyInstr.java
+++ b/core/src/main/java/org/jruby/ir/instructions/ProcessModuleBodyInstr.java
@@ -40,7 +40,7 @@ public Object interpret(ThreadContext context, StaticScope currScope, DynamicSco
         InterpretedIRBodyMethod bodyMethod = (InterpretedIRBodyMethod) getModuleBody().retrieve(context, self, currScope, currDynScope, temp);
 		RubyModule implClass = bodyMethod.getImplementationClass();
 
-        return bodyMethod.call(context, implClass, implClass, null, Block.NULL_BLOCK);
+        return bodyMethod.call(context, implClass, implClass, "<module>", Block.NULL_BLOCK);
     }
 
     @Override
diff --git a/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java b/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java
index b863fcb200b..b599d4fc109 100644
--- a/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java
+++ b/core/src/main/java/org/jruby/ir/interpreter/Interpreter.java
@@ -127,15 +127,15 @@ public static IRubyObject INTERPRET_BLOCK(ThreadContext context, Block block, IR
     }
 
     public static IRubyObject INTERPRET_CLASS(ThreadContext context, IRScope body, RubyModule clazz) {
-        return interpretFrameScope(context, null, body, clazz, null, Visibility.PUBLIC, clazz, null, null, Block.NULL_BLOCK);
+        return interpretFrameScope(context, null, body, clazz, null, Visibility.PUBLIC, clazz, "<class>", null, Block.NULL_BLOCK);
     }
 
     public static IRubyObject INTERPRET_MODULE(ThreadContext context, IRScope body, RubyModule clazz) {
-        return interpretFrameScope(context, null, body, clazz, null, Visibility.PUBLIC, clazz, null, null, Block.NULL_BLOCK);
+        return interpretFrameScope(context, null, body, clazz, null, Visibility.PUBLIC, clazz, "<module>", null, Block.NULL_BLOCK);
     }
 
     public static IRubyObject INTERPRET_METACLASS(ThreadContext context, IRScope body, RubyModule clazz, Visibility visibility) {
-        return interpretFrameScope(context, null, body, clazz, context.getCurrentScope(), visibility, clazz, null, null, Block.NULL_BLOCK);
+        return interpretFrameScope(context, null, body, clazz, context.getCurrentScope(), visibility, clazz, "<metaclass>", null, Block.NULL_BLOCK);
     }
 
     public static IRubyObject INTERPRET_METHOD(ThreadContext context, IRScope body, RubyModule implClass,
diff --git a/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java b/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
index 490878ddf92..55ff1941b8f 100644
--- a/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
+++ b/core/src/main/java/org/jruby/ir/runtime/IRRuntimeHelpers.java
@@ -1969,7 +1969,7 @@ public static void defCompiledInstanceMethod(ThreadContext context, MethodHandle
     public static IRubyObject invokeModuleBody(ThreadContext context, DynamicMethod method) {
         RubyModule implClass = method.getImplementationClass();
 
-        return method.call(context, implClass, implClass, null, Block.NULL_BLOCK);
+        return method.call(context, implClass, implClass, "<module>", Block.NULL_BLOCK);
     }
 
     @JIT
diff --git a/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java b/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
index bd1d780ada1..44cfebecdca 100644
--- a/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
+++ b/core/src/main/java/org/jruby/ir/targets/JVMVisitor.java
@@ -499,7 +499,7 @@ private void defineRunMethod(IRScriptBody script, String scopeName, String scope
         method.aconst_null(); // args
         method.getstatic(p(Block.class), "NULL_BLOCK", ci(Block.class)); // block
         method.aload(4); // self class
-        method.aconst_null(); // call name
+        method.ldc("<root>"); // call name
 
         method.invokestatic(clsName, scopeName, sig(signature.type().returnType(), signature.type().parameterArray()));
         method.areturn();
diff --git a/core/src/main/java/org/jruby/runtime/Frame.java b/core/src/main/java/org/jruby/runtime/Frame.java
index 2115584753c..8e61f9c484a 100644
--- a/core/src/main/java/org/jruby/runtime/Frame.java
+++ b/core/src/main/java/org/jruby/runtime/Frame.java
@@ -96,6 +96,7 @@ public final class Frame {
      * when needed.
      */
     public Frame() {
+        name = "<root>";
     }
 
     /**
@@ -112,6 +113,7 @@ private Frame(Block nullBlock) {
      */
     private Frame(Frame frame) {
         assert frame.block != null;
+        assert frame.name != null;
 
         this.self = frame.self;
         this.name = frame.name;
@@ -135,6 +137,7 @@ public void updateFrame() {
      * @param name The name of the method being called
      */
     public void updateFrame(String name) {
+        assert name != null;
         this.name = name;
     }
 
@@ -147,6 +150,7 @@ public void updateFrame(String name) {
     public void updateFrame(Frame frame) {
         Block block = frame.block;
         assert block != null;
+        assert frame.name != null;
 
         this.self = frame.self;
         this.name = frame.name;
@@ -165,6 +169,7 @@ public void updateFrame(Frame frame) {
      */
     public void updateFrame(RubyModule klazz, IRubyObject self, String name, Block block) {
         assert block != null;
+        assert name != null;
         this.self = self;
         this.name = name;
         this.klazz = klazz;
@@ -182,6 +187,7 @@ public void updateFrame(RubyModule klazz, IRubyObject self, String name, Block b
      */
     public void updateFrame(RubyModule klazz, IRubyObject self, String name, Visibility visibility, Block block) {
         assert block != null;
+        assert name != null;
         this.self = self;
         this.name = name;
         this.klazz = klazz;
@@ -196,7 +202,7 @@ public void updateFrame(RubyModule klazz, IRubyObject self, String name, Visibil
      */
     public void updateFrameForEval(IRubyObject self) {
         this.self = self;
-        this.name = null;
+        this.name = "<eval>";
         this.visibility = Visibility.PRIVATE;
     }
 
@@ -267,6 +273,7 @@ public void setKlazz(RubyModule klazz) {
      * @param name the new name
      */
     public void setName(String name) {
+        assert name != null;
         this.name = name;
     }