Better Diagnostic for Trait Object Capture
Part of #52663.
This commit enhances `LaterUseKind` detection to identify when a borrow
is captured by a trait object which helps explain why there is a borrow
error.
r? @nikomatsakis
cc @pnkfelix
codegen_llvm: verify that inline assembly operands are scalars
Another set of inline assembly fixes. This time let's emit an error message when the operand value cannot be coerced into the operand constraint.
Two questions:
1) Should I reuse `E0668` which was introduced in #54568 or just use `E0669` as it stands because they do mean different things, but maybe that's not too user-friendly. Just a thought.
2) The `try_fold` returns the operand which failed to be converted into a scalar value, any suggestions on how to use that in the error message?
Thanks!
NLL is missing struct field suggestion
Part of #52663.
This commit adds suggestions to change the definitions of fields in
struct definitions from immutable references to mutable references.
r? @nikomatsakis
cc @pnkfelix
Fix range literals borrowing suggestions
Fixes#54505. The compiler issued incorrect range borrowing suggestions (missing `()` around borrows of range literals). This was not correct syntax (see the issue for an example).
With changes in this PR, this is fixed for all types of `Range` literals.
Thanks again to @varkor and @estebank for their invaluable help and guidance.
r? @varkor
Prepare miri engine for enforcing validity invariant during execution
In particular, make recursive checking of references optional, and add a `const_mode` parameter that says whether `usize` is allowed to contain a pointer. Also refactor validation a bit to be type-driven at the "leafs" (primitive types), and separately validate scalar layout to catch `NonNull` violations (which it did not properly validate before).
Fixes https://github.com/rust-lang/rust/issues/53826
Also fixes https://github.com/rust-lang/rust/issues/54751
r? @oli-obk
Now when a `FnMut` closure is returning a closure that contains a
reference to a captured variable, we provide an error that makes it more
clear what is happening.
[NLL] Improve closure region bound errors
Previously, we would report free region errors that originate from closure with the span of the closure and a "closure body requires ..." message. This is now updated to use a reason and span from inside the closure.
Fix dead code lint for functions using impl Trait
Fixes https://github.com/rust-lang/rust/issues/54754
This is a minimal fix that doesn't add any new queries or touches unnecessary code. Please nominate for beta backport if wanted.
This commit updates the captured trait object search logic to look for
unsized casts to boxed types rather than for functions that returned
trait objects.
rustc: Allow `#[no_mangle]` anywhere in a crate
This commit updates the compiler to allow the `#[no_mangle]` (and
`#[export_name]` attributes) to be located anywhere within a crate.
These attributes are unconditionally processed, causing the compiler to
always generate an exported symbol with the appropriate name.
After some discussion on #54135 it was found that not a great reason
this hasn't been allowed already, and it seems to match the behavior
that many expect! Previously the compiler would only export a
`#[no_mangle]` symbol if it were *publicly reachable*, meaning that it
itself is `pub` and it's otherwise publicly reachable from the root of
the crate. This new definition is that `#[no_mangle]` *is always
reachable*, no matter where it is in a crate or whether it has `pub` or
not.
This should make it much easier to declare an exported symbol with a
known and unique name, even when it's an internal implementation detail
of the crate itself. Note that these symbols will persist beyond LTO as
well, always making their way to the linker.
Along the way this commit removes the `private_no_mangle_functions` lint
(also for statics) as there's no longer any need to lint these
situations. Furthermore a good number of tests were updated now that
symbol visibility has been changed.
Closes#54135
NLL: temps in block tail expression diagnostic
This change adds a diagnostic that explains when temporaries in a block tail expression live longer than block local variables that they borrow, and attempts to suggest turning the tail expresion into a statement (either by adding a semicolon at the end, when its result value is clearly unused, or by introducing a `let`-binding for the result value and then returning that).
Fix#54556
This commit updates the compiler to allow the `#[no_mangle]` (and
`#[export_name]` attributes) to be located anywhere within a crate.
These attributes are unconditionally processed, causing the compiler to
always generate an exported symbol with the appropriate name.
After some discussion on #54135 it was found that not a great reason
this hasn't been allowed already, and it seems to match the behavior
that many expect! Previously the compiler would only export a
`#[no_mangle]` symbol if it were *publicly reachable*, meaning that it
itself is `pub` and it's otherwise publicly reachable from the root of
the crate. This new definition is that `#[no_mangle]` *is always
reachable*, no matter where it is in a crate or whether it has `pub` or
not.
This should make it much easier to declare an exported symbol with a
known and unique name, even when it's an internal implementation detail
of the crate itself. Note that these symbols will persist beyond LTO as
well, always making their way to the linker.
Along the way this commit removes the `private_no_mangle_functions` lint
(also for statics) as there's no longer any need to lint these
situations. Furthermore a good number of tests were updated now that
symbol visibility has been changed.
Closes#54135
Remove unneccessary error from test, revealing NLL error.
Part of #52663.
Removes unnecessary type mismatch error from test that was hiding
borrow check error from NLL stderr.
r? @nikomatsakis
