Program: 134254
Project: 134254
Buggy source:
@Override protected boolean handleMessage(FMLInterModComms.IMCMessage message,boolean server,boolean runtime){
  if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String structurePath=cmp.getString("String_Node_Str");
    String structureID=cmp.getString("String_Node_Str");
    boolean generates=cmp.getBoolean("String_Node_Str");
    if (!StructureRegistry.registerStructure(new ResourceLocation(structurePath),structureID,generates))     getLogger().warn(String.format("String_Node_Str",structurePath,structureID));
    return true;
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String genPath=cmp.getString("String_Node_Str");
    String genID=cmp.getString("String_Node_Str");
    if (!GenericItemCollectionRegistry.register(new ResourceLocation(genPath),genID))     getLogger().warn(String.format("String_Node_Str",genPath,genID));
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    int dimensionID=cmp.getInteger("String_Node_Str");
    String[] types=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (types != null)     DimensionDictionary.registerDimensionTypes(dimensionID,Arrays.asList(types));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    int dimensionID=cmp.getInteger("String_Node_Str");
    String[] types=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (types != null)     DimensionDictionary.unregisterDimensionTypes(dimensionID,Arrays.asList(types));
 else     DimensionDictionary.unregisterDimensionTypes(dimensionID,null);
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    DimensionDictionary.registerType(message.getStringValue());
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String type=cmp.getString("String_Node_Str");
    String[] subtypes=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (type != null)     DimensionDictionary.registerSubtypes(type,Arrays.asList(subtypes));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String type=cmp.getString("String_Node_Str");
    String[] subtypes=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (type != null)     DimensionDictionary.registerSupertypes(type,Arrays.asList(subtypes));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
  return false;
}

Fixed version (ground truth):
@Override protected boolean handleMessage(FMLInterModComms.IMCMessage message,boolean server,boolean runtime){
  if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String structurePath=cmp.getString("String_Node_Str");
    String structureID=cmp.getString("String_Node_Str");
    boolean generates=cmp.getBoolean("String_Node_Str");
    if (!StructureRegistry.registerStructure(new ResourceLocation(structurePath),structureID,generates))     getLogger().warn(String.format("String_Node_Str",structurePath,structureID));
    return true;
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String genPath=cmp.getString("String_Node_Str");
    String genID=cmp.getString("String_Node_Str");
    if (!GenericItemCollectionRegistry.register(new ResourceLocation(genPath),genID))     getLogger().warn(String.format("String_Node_Str",genPath,genID));
    return true;
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    int dimensionID=cmp.getInteger("String_Node_Str");
    String[] types=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (types != null)     DimensionDictionary.registerDimensionTypes(dimensionID,Arrays.asList(types));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
 else   if (isMessage("String_Node_Str",message,NBTTagCompound.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    int dimensionID=cmp.getInteger("String_Node_Str");
    String[] types=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (types != null)     DimensionDictionary.unregisterDimensionTypes(dimensionID,Arrays.asList(types));
 else     DimensionDictionary.unregisterDimensionTypes(dimensionID,null);
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    DimensionDictionary.registerType(message.getStringValue());
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String type=cmp.getString("String_Node_Str");
    String[] subtypes=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (type != null)     DimensionDictionary.registerSubtypes(type,Arrays.asList(subtypes));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
 else   if (isMessage("String_Node_Str",message,String.class)) {
    NBTTagCompound cmp=message.getNBTValue();
    String type=cmp.getString("String_Node_Str");
    String[] subtypes=IvNBTHelper.readNBTStrings("String_Node_Str",cmp);
    if (type != null)     DimensionDictionary.registerSupertypes(type,Arrays.asList(subtypes));
 else     getLogger().warn("String_Node_Str" + message.key + "String_Node_Str");
    return true;
  }
  return false;
}