Is it possible to compile a Package on ARMv8 and run it on ARMv7 ?
I am not really experienced in the whole building thing (yet). I came to this question because my Odroid C1+ fails to compile icinga2 due to the very limited RAM. The C2 has 2 GB of RAM and will do probably better at this task.
But can I run a C2 (ARMv8) compiled package on my C1+ (ARMv7)?
Is it possible to compile a Package on ARMv8 and run it on ARMv7 ?
That's called cross-compiling and is the usual way how ARM code is generated – only that most build machines for ARM binaries are probably x86_64 nowadays. But if you have a compiler that targets platform ARMv7 running on ARMv8, I don't see a problem.
I am not really experienced in the whole building thing (yet). I came to this question because my Odroid C1+ fails to compile icinga2 due to the very limited RAM. The C2 has 2 GB of RAM and will do probably better at this task.
You know what is much much better at compiling? A proper PC with more than 4GB of RAM, massive RAM bandwidth and a much higher storage bandwidth, with a heavily pipelined multicore CISC CPU rather than an energy-efficient ARM.
Really, software for embedded systems is usually built on non-embedded computers with cross-compilers. There's definitely different ways to cross-compile something for your C1+ on your PC; I'd generally recommend using the method your Linux distro (if you're using any) has for cross-compiling packages.
ARMv7 is a different platform from ARMv8, so compiling software from ARMv7 on v8 has no advantage over compiling software for ARMv7 on x86. You'll need a cross-compiling toolchain, anyway.