[clang] [clang] Fix crash when declaring invalid lambda member (PR #74110)

[Aaron Ballman via cfe-commits]

https://github.com/AaronBallman commented:

The changes should come with a release note in clang/docs/ReleaseNotes.rst.

I'm confused -- the patch says that it's fixing a crash, but none of those test cases crash today. Can you add some new test coverage that demonstrates the crash? Also, the changes are to code that's only run in asserts builds... so why are we getting more diagnostics after these changes?

https://github.com/llvm/llvm-project/pull/74110