Nope. Rust stabilized strict provenance over a year ago. Some details about aliasing aren't tied down, but so long as you can obey the strict provenance rules you're golden today in Rust to hide flags in pointers etc.
LLVM is quite sure that, for example, two pointers to different objects are different. That's true even if in fact the objects both lived in the exact same spot on the stack (but at different times). That's... well it's not what Rust wants but it's not necessarily an unacceptable outcome and Rust could just ask for their addresses and compare those...
Except it turns out if we ask for their addresses, which are the same integer, LLVM remembers it believed the pointers were different and insists those are different too.
Until you call its bluff and do arithmetic on them. Then, in some cases, it snaps out of it and remembers that they're identical...
This is a compiler bug, but, apparently it's such a tricky bug to fix that I stopped even looking to see whether they'd fixed it after a few years... It affects C, C++, Rust, all of them as a result can be miscompiled by a compiler using LLVM [it's easiest to demonstrate this bug with Rust but it's the same in every language]. But as you've probably noticed, this doesn't have such an enormous impact that anybody stopped using LLVM.
https://blog.rust-lang.org/2025/01/09/Rust-1.84.0/#strict-pr...