Is it usually best to compile on the same machine you want to execute on?

Question

(Note: I'm just using ffmpeg as an example, I have often wondered the same thing with other programs)

I have a build script for ffmpeg which compiles in support for a few non-standard features. Now I want to use that encoder on several other machines. Is it OK just to copy the /usr/local/bin/ffmpeg executable over, or should I prefer to run the build script on the other machines?

• Are there likely to be any hardware-dependent optimisations in the compilation?
• Is it possible to have any hidden dependencies which I also need to copy, apart from the executable itself and anything I can find with ldd?

Answer 1

yes and yes :)

if you want your compiled binary to run on a number of machines, you have to compile it in a way that it matches the architecture and setup (library-wise) on these machines. that normally means:

• link everything you can statically
• ship the libs your binary needs
• 32bit stuff runs on 64bit machines, but not the other way around

so, if you do not want to think about if it might run or if it wont: compile and link the binary on the machine you want it to run.