I think that only re-linking should be required if you only change source files and not headers. Headers implicitly convey are the sizes, inheritance and other

I think that only re-linking should be required if you only change source files and not headers. Headers implicitly convey are the sizes, inheritance and other stuff that dependencies need for compilation. I suppose you could have some extra aggressive optimizations that force inlining, but I haven't seen a need for this, even in game dev.