Hi, I have done some work on gcc-6502 to support the Atari executable format and some other small support stuff and bug fixes. If you want to try it out, try the following: https://github.com/ivop/gcc-6502-bits
$ git clone https://github.com/ivop/gcc-6502-bits.git
$ cd gcc-6502-bits
$ git clone https://github.com/ivop/gcc-6502.git gcc-src
$ CC65_PATH=/path/to/your/cc65/bin ./build.sh 2>&1 | tee build.log
Now you should have a 6502-gcc toolchain in prefix/bin. cc65 is used as "bin