Linker option to compute executable size?

I’m writing an interpreter, and want to construct the executable so that the interpreter’s source code can be appended to the executable. To do this, i need to know how large the executable was when the linker wrote it to disk.

I’ve dug around and googled up a lot of not-workable approaches. It seems like the linker should have some predefined constant for “final module size” or suchlike, but i’m not finding anything that looks like that. I’m a bit leery of approaching the SECTIONS business of the linker but maybe that’s the only thing left.

Has anyone gone through this exercise? TIA.