[clang] [Clang] Enable -fpointer-tbaa by default. (PR #117244)

[Joshua Cranmer via cfe-commits]

jcranmer-intel wrote:

> do other tools like UBSan (etc) help users to find and fix the issues?

We don't yet have a reliable tool for sanitizing TBAA failures. There is a project to do that (the TypeSanitizer, see https://discourse.llvm.org/t/reviving-typesanitizer-a-sanitizer-to-catch-type-based-aliasing-violations/66092), but the last time I tried using the TypeSanitizer, it wasn't ready for production use.

https://github.com/llvm/llvm-project/pull/117244