nll type annotations in multisegment path
This turned out to be sort of tricky. The problem is that if you have a path like
```
<Foo<&'static u32>>::bar
```
and it comes from an impl like `impl<T> Foo<T>` then the self-type the user gave doesn't *directly* map to the substitutions that the impl wants. To handle this, then, we have to preserve not just the "user-given substs" we used to do, but also a "user-given self-ty", which we have to apply later. This PR makes those changes.
It also removes the code from NLL relate-ops that handled canonical variables and moves to use normal inference variables instead. This simplifies a few things and gives us a bit more flexibility (for example, I predict we are going to have to start normalizing at some point, and it would be easy now).
r? @matthewjasper -- you were just touching this code, do you feel comfortable reviewing this?
Fixes#54574
Make `bad_style` a silent alias for `nonstandard_style`
Now only `nonstandard_style` is suggested in `rustc -W help`, but `bad_style` will not produce a warning. Closes#41646.
r? @Manishearth
A few iterator-related improvements
- typeck: don't collect into a vector when unnecessary
- create only one vector when winnowing candidates
- change a cloning map to `into_iter`
Exit with code 101 on fatal codegen errors
Fixes#54992.
This PR installs a custom fatal error handler that prints the error from LLVM and exits with 101. There should be no visible change in the output from LLVM. This allows distinguishing a fatal LLVM error with a compilation error by exit code.
This PR also modifies the LLVM codegen backend to ICE instead of emitting a fatal error when encountering a LLVM worker thread panic for the same reason.
r? @cuviper
At some point, I had thought to use this code to handle equality
comparisons for the `IfEq` verify bounds; at that point, we might not
have had an infcx to talk about. But we wound up doing "SCC
representatives" instead, so that's fine.
clarify pointer add/sub function safety concerns
Ralf Jung made the same changes to the offset functions' documentation
in commit fb089156. As add/sub just call offset, the same limitation
applies here, as well.
I did not copy the whole explanation ("In particular, the resulting pointer may *not* be used to access a different allocated object [...]") because I'd consider that as being too repetitive. The documentation of add/sub already refers to the offset function, so people interested in the details can look it up, there.
But changing 'an object' to 'the same object' is a small change which improves clarity a lot.
Add missing lifetime fragment specifier to error message.
A very minor issue, `lifetime` was missing from the error list.
I left `literal` in the list, even though it is unstable. It looks like it may stabilize soon anyways.
Cleanup rustc/session
- improve allocations
- improve common patterns
- use `to_owned` when no string conversion is needed
- move `const`s up to improve readability
- whitespace & formatting improvements
second round of refactorings for universes
A second round of (what I believe to be) "no functional change" refactorings, taken from my universes branch.
r? @scalexm
Instead, we talk about:
- creating the "next" universe
- universes "extending" one another
- and `u1.can_name(u2)`, meaning that `u1` contains all names from `u2`
