Handle panicking like rustc CTFE does
Instead of using `core::fmt::format` to format panic messages, which may in turn panic too and cause recursive panics and other messy things, redirect `panic_fmt` to `const_panic_fmt` like CTFE, which in turn goes to `panic_display` and does the things normally. See the tests for the full call stack.
The tests don't work yet, I probably missed something in minicore.
fixes#16907 in my local testing, I also need to add a test for it
Instead of using `core::fmt::format` to format panic messages, which may in turn
panic too and cause recursive panics and other messy things, redirect
`panic_fmt` to `const_panic_fmt` like CTFE, which in turn goes to
`panic_display` and does the things normally. See the tests for the full
call stack.
In the evaluation of const values of recursive types
certain declarations could cause an endless call-loop
within the interpreter (hir-ty’s create_memory_map),
which would lead to a stack overflow.
This commit adds a check that prevents values that contain
an address in their value (such as TyKind::Ref) from being
allocated at the address they contain.
The commit also adds a test for this edge case.
Add fuel to match checking
Exhaustiveness checking is NP-hard hence can take extremely long to check some specific matches. This PR makes ehxaustiveness bail after a set number of steps. I chose a bound that takes ~100ms on my machine, which should be more than enough for normal matches.
I'd like someone with less recent hardware to run the test to see if that limit is low enough for them. Also curious if the r-a team thinks this is a good ballpark or if we should go lower/higher. I don't have much data on how complex real-life matches get, but we can definitely go lower than `500 000` steps.
The second commit is a drive-by soundness fix which doesn't matter much today but will matter once `min_exhaustive_patterns` is stabilized.
Fixes https://github.com/rust-lang/rust-analyzer/issues/9528 cc `@matklad`
