Same here, make clean && make bigide fixed problem
I just now rebuilt/reinstalled
fpc and
lazarus trunk.
I use a script that does a git pull for me to get the latest changes for me, but then I have it clone that local repo into a fresh repo locally to do the builds in, so I don't ever do to a make clean anymore for my rebuilds/re-installs.
make bigide and subsequent reinstall worked without any issues on the
fpc built/installed immediately before it.