Do not emit type errors after parse error in last statement of block
When recovering from a parse error inside a block, do not emit type
errors generating on that block's recovered return expression.
Fix#57383.
Make struct_tail normalize when possible
As noted in commit message: this replaces the existing methods to extract the struct tail(s) with new entry points that make the handling of normalization explicit.
Most of the places that call `struct_tail` are during codegen, post type-checking, and therefore they can get away with using `tcx.normalize_erasing_regions` (this is the entry point `struct_tail_erasing_lifetimes`)
For other cases that may arise, one can use the core method, which is parameterized over the normalization `Ty -> Ty` closure (`struct_tail_with_normalize`).
Or one can use the trivial entry point that does not normalization (`struct_tail_without_normalization`)
----
I spent a little while trying to make a test that exposed the bug via `impl Trait` rather than a projection, but I failed to find something that tripped up the current nightly `rustc`.
* I have *not* spent any time trying to make tests that trip up the other places where `struct_tail` was previously being called. While I do think the task of making such tests could be worthwhile, I am simply running out of time. (Its also possible that the layout code is always the first point called, and thus it may be pointless to try to come up with such tests.)
I also spent a little time discussing with @eddyb where this code should live. They suggested moving `struct_tail` and its sibling `struct_lockstep_tails` to the `LayoutCx`. But in the interest of time, I have left that refactoring (which may be questionable at this point) to a follow-up task.
----
Fix#60431
Replace unsafe_destructor_blind_to_params with may_dangle
This PR will completely remove support for `#[unsafe_destructor_blind_to_params]` attribute,
which is deprecated in #38970 by `[may_dangle]` unsafe attribute.
Closes#34761
rustc_mir: follow FalseUnwind's real_target edge in qualify_consts.
As far as I can tell, this was accidentally omitted from #47802.
Fixes#62272.
r? @matthewjasper or @nikomatsakis
This is a way to address the regression aspect of rust-lang/rust#62614 in the
short term without actually fixing the bug. (My thinking is that the bug that
this lint detects has gone undetected for this long, it can wait a bit longer
until I or someone else has a chance to put in a proper fix that accounts for
rust-lang/rust#62614.)
Rollup of 5 pull requests
Successful merges:
- #62275 (rustc_mir: treat DropAndReplace as Drop + Assign in qualify_consts.)
- #62465 (Sometimes generate storage statements for temporaries with type `!`)
- #62481 (Use `fold` in `Iterator::last` default implementation)
- #62493 (#62357: doc(ptr): add example for {read,write}_unaligned)
- #62532 (Some more cleanups to syntax::print)
Failed merges:
r? @ghost
Add a test for the issue resolved by removing `resolve_macro_path`
Add a test making sure that extern prelude entries introduced from an opaque macro are not visible anywhere, even it that macro
Fix test output after rebase
It's more convenient to have all this highly related stuff together on one screen (for future refactorings).
The `expand_invoc` function is compact enough now, after all the previous refactorings.
Remove a bunch of `Option`s that assumed that dummy fragment creation could fail.
The test output changed due to not performing the expansion in `fn expand_invoc` in case of the recursion limit hit.
Ok, it's hard to explain what happens, but identifier's hygienic contexts need to be "adjusted" to modules/scopes before they are resolved in them.
To be resolved in all kinds on preludes the identifier needs to be adjusted to the root expansion (aka "no expansion").
Previously this was done for the `macro m() { ::my_crate::foo }` case, but forgotten for all other cases.
Also move macro stability checking closer to other checks performed on obtained resolutions.
Tighten the stability spans as well, it is an error to *refer* to and unstable entity in any way, not only "call" it.
This way we are processing all of them in a single point, rather than separately for each syntax extension kind.
Also, the standard expected/found wording is used.
It either returns the indeterminacy error, or valid (but perhaps dummy) `SyntaxExtension`.
With this change enum `Determinacy` is no longer used in libsyntax and can be moved to resolve.
The regressions in diagnosics are fixed in the next commits.
Create real working and registered (even if dummy) `SyntaxExtension`s for them.
This improves error recovery and allows to avoid all special cases for proc macro stubs (except for the error on use, of course).
The introduced dummy `SyntaxExtension`s can be used for any other inappropriately resolved macros as well.
