Update arm gcc to the latest version.

[cmaglie]

There are actually two distribution of arm-gcc-none-eabi, one from CodeSourcery:
http://www.mentor.com/embedded-software/sourcery-tools/sourcery-codebench/editions/lite-edition/

and one from ARM:
https://launchpad.net/gcc-arm-embedded

Arduino Due uses an old version 4.4.1 from CodeSourcery. Replacing it with the latest 4.7.3 works flawlessy, but unfortunately CodeSourcery doesn't provide prebuilt binaries for MacOS or Linux64 and building it from sources is very hard.

On the other side ARM provides binaries also for MacOSX and building the Linux64 version is easily done by following their instructions. Unfortunately the compiler didn't work as expected: the Blink sketch produced by gcc, for some reason, doesn't run on the Due board.

[cmaglie]

Paul Stoffregen blog post "GNU Toolchain Cross-Compile Challenges"

http://dorkbotpdx.org/blog/paul/gnu_toolchain_crosscompile_challenges

C

[masoncj]

I would really love to help this happen, specifically for lambda support, which I'm using for a new library for BLE. The launchpad toolchain works flawlessly for me on all the chips/boards I've tried (teensy 3, mchck, nrf51822, etc), but I don't have a Due to test on.

Paul's toolchain also works fine for me.

How can I help?

[cmaglie]

@cmason1978
well, you just did by saying "The launchpad toolchain works flawlessly for me".
I've re-tested the launchpad toolchain and it works :-o (I surely made some trivial mistake during my first test).

I can schedule this issue for the Arduino IDE 1.5.6 (or even 1.5.5, I need to do some more tests let's see).

The Blink compiled with launchpad is bigger, about 12.7K against the 10.4K of CodeSourcery.
How is this possible? Are there some compiler flags that can be enabled to save some space? Or is the CodeSourcery that has some optimizations missing in the launchpad release? Do you have any clue?

C

[cmaglie]

Merged in #1813. To be released in Arduino IDE 1.5.7.