Register allocator performing worse in avr-gcc-5.x?
there's one thing I have noticed when compiling with avr-gcc-5.2.0, and it is
that compared to avr-gcc.4.8.1, it generates larger binaries and optimizes
worse, while using identical compilation flags, especially when under high
The 5.2.0 version spills many registers, while the 4.8.1 has no
need to do so. I'd appreciate if you could have a look into this.
About the "volatile" keyword in front of the global register variable:
Feel free to try what happens when you remove this keyword. That in itself
is interesting, and this behaviour is exhibited by both compiler versions.