Due to the organization of our codebase we tend to build and link in a bunch of functions into the binaries that aren't actually used.

I've tried building with -ffunction-sections -fdata-sections -Wl,--gc-sections, and it reduces bitcoind (after stripping) from 7.2 MB to 6.9 MB. The bitcoin-wallet tool goes from 3.5 MB to 1.3 MB.

Any reason why we don't do this? I only find a mention in #4042, but it's not clear how relevant that is to me.