Porting to EFM32

Great! The Linker file thing sounds like a pain - perhaps it could only generate it if the path was in the gen directory?

For the _sbrk and _etext, I'd have though that would only happen if code used malloc - which it shouldn't. Perhaps you could look in gen/platform_config.h and see if JS_VAR_CACHE_SIZE is set (it should be) - you definitely shouldn't have RESIZABLE_JSVARS as that is what is used when running under something like Linux.