Inventables Fork of grbl too large 32,266 bytes when compiled

Continuing the discussion from Z axis was erratic…now I've got bigger problems:


I have the Arduino IDE version 1.6.11 installed on a Windows 7 machine. When compiling the Inventables fork (as of 8/31/2016) the following error occurs.

On the same machine I then run the Arduino IDE version 1.6.8 from a USB drive with the following results:

[Edit] I have compiled other projects with the 1.6.11 and the 1.6.8 versions without any change in code size.


Yep, That’s what I got!

Looks like you can duplicate the issue by downloading the most current IDE and then build. This for me was 2 bytes short of being over(Verification not upload. Not at my machine).

You can then go into board manager tools -> boards -> board manager. Anything >= 1.6.12 will ballon the size. Where as 1.6.11 is 30,072 bytes. So looks like an issue that needs to be reported to

Ok so I have looked at the definition that gets downloaded with the boards and there are some differences.
You can download the 2 versions here

I have done a difference check on the 2 and the following changes
avr\ 2 is 1.6.12 and avr is 1.6.11
Files /Users/geoff/Downloads/avr/.DS_Store and /Users/geoff/Downloads/avr 2/.DS_Store differ Files /Users/geoff/Downloads/avr/bootloaders/.DS_Store and /Users/geoff/Downloads/avr 2/bootloaders/.DS_Store differ Files /Users/geoff/Downloads/avr/cores/.DS_Store and /Users/geoff/Downloads/avr 2/cores/.DS_Store differ Files /Users/geoff/Downloads/avr/cores/arduino/Print.cpp and /Users/geoff/Downloads/avr 2/cores/arduino/Print.cpp differ Files /Users/geoff/Downloads/avr/cores/arduino/Stream.h and /Users/geoff/Downloads/avr 2/cores/arduino/Stream.h differ Files /Users/geoff/Downloads/avr/cores/arduino/USBCore.cpp and /Users/geoff/Downloads/avr 2/cores/arduino/USBCore.cpp differ Files /Users/geoff/Downloads/avr/cores/arduino/USBCore.h and /Users/geoff/Downloads/avr 2/cores/arduino/USBCore.h differ Files /Users/geoff/Downloads/avr/cores/arduino/WString.cpp and /Users/geoff/Downloads/avr 2/cores/arduino/WString.cpp differ Files /Users/geoff/Downloads/avr/cores/arduino/WString.h and /Users/geoff/Downloads/avr 2/cores/arduino/WString.h differ Files /Users/geoff/Downloads/avr/libraries/SoftwareSerial/src/SoftwareSerial.h and /Users/geoff/Downloads/avr 2/libraries/SoftwareSerial/src/SoftwareSerial.h differ Files /Users/geoff/Downloads/avr/libraries/Wire/src/utility/twi.c and /Users/geoff/Downloads/avr 2/libraries/Wire/src/utility/twi.c differ Files /Users/geoff/Downloads/avr/platform.txt and /Users/geoff/Downloads/avr 2/platform.txt differ Files /Users/geoff/Downloads/avr/variants/ethernet/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/ethernet/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/gemma/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/gemma/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/leonardo/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/leonardo/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/mega/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/mega/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/robot_control/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/robot_control/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/robot_motor/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/robot_motor/pins_arduino.h differ Files /Users/geoff/Downloads/avr/variants/standard/pins_arduino.h and /Users/geoff/Downloads/avr 2/variants/standard/pins_arduino.h differ
I need to get some of my own work done right now so if anyone wants to find what has changed enough to take 2,184 bytes go for it.



I down rev’d Arduino AVR Boards to 1.6.11 and it did fix the problem on my machine.

Thanks, Geoff

Opened issue at


Nice work guys, glad we got to the bottom of this (even more glad it isn’t a grbl issue).

Thanks for all your help, everyone! This will help us with future issues, and now we have a viable solution for customers.

Your efforts are much appreciated!

I hope I don’t discover any more problems for you guys! :slight_smile: :slight_smile:

Sometimes I am an accident waiting to happen!!


I know this is a little late, but I compiled the inventables fork of GRBL on the 1.6.12 version (latest version) of the Arduino IDE on windows 10, 64 bit with no size issues.

I actually tested every version of grbl with no size issues.