:avr-gcc -vUsing built-in specs....gcc version 4.3.2 (GCC)
I can't speak for the Arduino team, but note that the Arduino IDE does not include "gcc" directly; instead, it's based on the "packaged" development environments (WinAVR for windows, AVR Crosspack for Mac, I think.) So to go to 4.7, we probably need the following to happen first:1) Atmel goes to 4.7 for AVR Studio (AVR Studio 6 has 4.6.2, for reasons that aren't clear.)2) "someone" puts together a WINAVR-like for Windows (non-AVR Studio) (hopefully with the same versions of binutils/avr-libc/gcc as AVR Studio)3) "someone" puts together a similar package for Mac.4) The Arduino team changes, tests, and becomes satisfied that the Arduino core works with the new compiler (those named memory spaces may sound good, but I think they're significantly incompatible with the way PROGMEM is currently used in the Arduino core.)(meanwhile, the linux distributions have been throwing together avr-gcc packages somewhat randomly, and frequently in ways that apparently don't work very well. Watching the Arduino project has made me appreciate the effort that goes into putting together "tool packages", a lot more than I used to. Especially since it's not getting done :-( (WINAVR and AVR Crosspack are both quite old.))Note that many of the intermediate versions between 4.3.2 and 4.7 have "known problems" WRT AVR and/or arduino. That hasn't helped, either.
Note that the gcc that Atmel is shipping with their AtmelStudio is only at 4.6.something...One of the changes in 4.7 is "named address spaces" that will, in theory, greatly simply storing constants in program memory. In reality, it may also break the current Arduino core code that uses <pgmspace.h>