pert:
OK, I figured you either meant 3rd party boards or 3rd party IDEs. Teensy are 3rd party boards and Teensyduino might be considered a 3rd party IDE because of the way it modifies the Arduino IDE (though not really that significantly), so Teensy is a bit of both.Is this the elsewhere?:
Determining the board type being used, revisited - Programming Questions - Arduino Forum
If the problem is with getting platform.local.txt working with Eclipse, I'll take your word that it doesn't work. But I just verified that platform.local.txt does work with Teensyduino. The location you need to place platform.txt is {Teensyduino installation folder/hardware/teensy/avr. One tricky thing with the Teensy board package is that it doesn't provide those handy "extra_flags" properties for customizing the compilation recipes. You can add those properties into the compilation recipes if you like. Or you could just override the complete compilation recipes in your platform.local.txt. Either one will be a bit more work to maintain, as you'll need to either reimplement the "extra_flags" modifications in platform.txt after every Teensyduino update if you did the former, or make sure to port any changes that were made to the compilation recipes to your platform.local.txt if you did the latter.
Yes, that's the elsewhere. I raised a bug against Eclipse CDT which makes it their problem, I'll take a look at Teensyduino as per your comments- thanks for that.
MarkMLl