[clang] [analyzer][solver] On SymSym RelOps, check EQClass members for contradictions (PR #71284)

[Balazs Benics via cfe-commits]

steakhal wrote:

> I'm not opposed to landing this PR in llvm-18 (we have it, and it improves the user experience), but I wouldn't like to have it in llvm-19 and later.

To clarify my intentions, I wanted to land this as it resolves user complaints (as fixing an open issue), at a likely reasonable runtime cost. I don't plan to work on the constraint manager for llvm-19 or later.
Given this, if we merge this, it will likely remain like that for a long time. If we don't merge this, we have the option for merging it for the next release cycle, but the questions and problems still remain, so why did we postpone this?

Personally, I'd say if there are no serious drawbacks for merging this, we should merge it.
We would still have plenty of time to revert if we wanted to.

Should we merge it?

https://github.com/llvm/llvm-project/pull/71284