clang-tidy killed by OOM?

Hi.

Since a few days, I notice that clang-tidy built from trunk consumes *a
lot* of memory, until the OOM killer kils it. I've tried it on two
projects now with the same symptom. Anyone else noticed this? It feels
like someone should have noticed, so I am suspecting a local problem.
However, I have built trunk locally in the past successfully several times. Any idea
what I could be doing wrong?

I am calling clang-tidy like:
$ /path/to/llvm/build/bin/clang-tidy -p /path/to/build/dir /path/to/file.cpp

Can you bisect the set of checks and figure out which check is that?