…id ICE

…lan-DPC

clean up E0275 explanation

r? @Dylan-DPC

Add long error code explanation message for E0637

Reference issue [rust-lang#61137](rust-lang#61137)
To incorporate a long error description for E0637, I have made the necessary modification to error_codes.rs and added error_codes/E0637.md, and blessed the relevant .stderror files. ~~, however when I build rustc stage 1, I am unable to make `$ rustc --explain E0637` work even though rustc appears to be able to call up the long error explanations for other errors. I wanted to guarantee this would work before moving on the blessing the various ui tests that have been affected. @GuillaumeGomez Do you know the most likely reason(s) why this would be the case?~~
Update: `$ rustc --explain E0637` works now.

…ic-activity-args, r=wesleywiser

self-profile: Support arguments for generic_activities.

This PR adds support for recording arguments of "generic activities". The most notable use case is LLVM module names, which should be very interesting for `crox` profiles. In the future it might be interesting to add more fine-grained events for pre-query passes like macro expansion.

I tried to judiciously de-duplicate existing self-profile events with `extra_verbose_generic_activity`, now that the latter also generates self-profile events.

r? @wesleywiser

…=Centril

Make ASCII ctype functions unstably const

Makes the following inherent methods on `u8` and `char` unstable `const fn`:

 * `is_ascii_alphabetic`
 * `is_ascii_uppercase`
 * `is_ascii_lowercase`
 * `is_ascii_alphanumeric`
 * `is_ascii_digit`
 * `is_ascii_hexdigit`
 * `is_ascii_punctuation`
 * `is_ascii_graphic`
 * `is_ascii_whitespace`
 * `is_ascii_control`

cc rust-lang#68983

…lan-DPC

Clean up E0283 explanation

r? @Dylan-DPC

change an instance of span_bug() to struct_span_err() to avoid ICE

After rust-lang#67148, the `span_bug()` in `parse_ty_tuple_or_parens()` is reachable because `parse_paren_comma_seq()` can return an `Ok()` even in cases where it encounters an error.
This pull request prevents an ICE in such cases by replacing the `span_bug()` with `struct_span_error()`.

Fixes rust-lang#68890.