View Full Version : Problem with 'multiple definition of Serial' on Windows Vista

11-29-2012, 11:49 PM
Hey all,

I'm running Teensy 3.0 under Arduino 1.02. I can't compile anything because I'm getting this error:

usb_inst.cpp.o:C:\Users\v\Downloads\arduino-1.0.2-teensy3-beta8-windows\arduino-1.0.2\hardware\teensy\cores\teensy3\/Print.h:21: multiple definition of `Serial'
main.cpp.o:C:\Users\v\Downloads\arduino-1.0.2-teensy3-beta8-windows\arduino-1.0.2\hardware\teensy\cores\teensy3\/Print.h:21: first defined here
collect2: ld returned 1 exit status

Any ideas on how to proceed? It's Vista ... ugh.



11-30-2012, 01:00 AM
That's very strange.

Could you please turn on verbose messages when compiling and post the verbose version, and also post the sketch you're trying to compile?

The "verbose when compiling" option is in File > Preferences. Please quit and restart Arduino before doing the run where you copy & paste the output, so it will start fresh and recompile everything.

11-30-2012, 01:02 AM
When you see the verbose messages, there are some harmless warning about violating strict aliasing. Don't be alarmed. That's normal.

11-30-2012, 07:14 AM
Thanks Paul for the quick reply!
I actually wiped all of my old versions of Arduino along with their libraries, and after restarts and working with the Windows USB serial installer linked on the Teensy page, finally got this to work! Now I'm happily working that 32-bit core ... :]

12-16-2012, 04:34 AM
I have the same issue but I can't figure out how to correct it.
Windows 7, 32 bit core, same error, same board and version of the software.

I don't have any old versions to wipe out. I installed the serial installer... I'm at a road block.

If I compile a blank sketch, I get the same error. It doesn't matter if the board is plugged in or not. It says COM 3.

I delete the the folder, re-extrated everything, and reran teensyduino again...No change.

I didn't have to choose which Teensy I was using this time....

12-16-2012, 02:46 PM
Ok, I figured it out.

The solution is to NOT follow the install instructions or Tutorials for 1st use. They're apparently only for the Teensy 1 and 2.

Don't download the Teensy application and don't use teensyduino.
Only install the serial install and extract the arduino-1.0.2-teensy3.

12-19-2012, 04:34 PM
This information needs to be on the teensy 3.0 main page, and in bold letters on the teensyduino page.

12-20-2012, 09:58 AM
I've added a message to the Teensyduino download page, with "Teensy 3.0" in bold and red text.