This alters the borrow checker's requirements on invoking closures from
requiring an immutable borrow to requiring a unique immutable borrow. This means
that it is illegal to invoke a closure through a `&` pointer because there is no
guarantee that is not aliased. This does not mean that a closure is required to
be in a mutable location, but rather a location which can be proven to be
unique (often through a mutable pointer).
For example, the following code is unsound and is no longer allowed:
type Fn<'a> = ||:'a;
fn call(f: |Fn|) {
f(|| {
f(|| {})
});
}
fn main() {
call(|a| {
a();
});
}
There is no replacement for this pattern. For all closures which are stored in
structures, it was previously allowed to invoke the closure through `&self` but
it now requires invocation through `&mut self`.
The standard library has a good number of violations of this new rule, but the
fixes will be separated into multiple breaking change commits.
Closes#12224
This alters the borrow checker's requirements on invoking closures from
requiring an immutable borrow to requiring a unique immutable borrow. This means
that it is illegal to invoke a closure through a `&` pointer because there is no
guarantee that is not aliased. This does not mean that a closure is required to
be in a mutable location, but rather a location which can be proven to be
unique (often through a mutable pointer).
For example, the following code is unsound and is no longer allowed:
type Fn<'a> = ||:'a;
fn call(f: |Fn|) {
f(|| {
f(|| {})
});
}
fn main() {
call(|a| {
a();
});
}
There is no replacement for this pattern. For all closures which are stored in
structures, it was previously allowed to invoke the closure through `&self` but
it now requires invocation through `&mut self`.
The standard library has a good number of violations of this new rule, but the
fixes will be separated into multiple breaking change commits.
Closes#12224
[breaking-change]
This exposes volatile versions of the memset/memmove/memcpy intrinsics.
The volatile parameter must be constant, so this can't simply be a
parameter to our intrinsics.
Now with proper checking of enums and allows unsized fields as the last field in a struct or variant. This PR only checks passing of unsized types and distinguishing them from sized ones. To be safe we also need to control storage.
Closes issues #12969 and #13121, supersedes #13375 (all the discussion there is valid here too).
This currently requires linking against a library like libquadmath (or
libgcc), because compiler-rt barely has any support for this and most
hardware does not yet have 128-bit precision floating point. For this
reason, it's currently hidden behind a feature gate.
When compiler-rt is updated to trunk, some tests can be added for
constant evaluation since there will be support for the comparison
operators.
Closes#13381
This exposes volatile versions of the memset/memmove/memcpy intrinsics.
The volatile parameter must be constant, so this can't simply be a
parameter to our intrinsics.
This patch adds a special rule for `Unsafe<T>` and makes it `Share`
regardless of whether T is `Share`.
[breaking-change]
Closes#13125
cc @nikomatsakis
When reporting "consider removing this semicolon" hint message, the
offending semicolon may come from macro call site instead of macro
itself. Using the more appropriate span makes the hint more helpful.
Closes#13428.
This gives a better NOTE error message when a privacy error is encountered with
a static method. Previously no note was emitted (due to lack of support), but
now a note is emitted indicating that the struct/enum itself is private.
Closes#13641
Refactors all uses of ty_vec and associated things to remove the vstore abstraction (still used for strings, for now). Pointers to vectors are stored as ty_rptr or ty_uniq wrapped around a ty_vec. There are no user-facing changes. Existing behaviour is preserved by special-casing many instances of pointers containing vectors. Hopefully with DST most of these hacks will go away. For now it is useful to leave them hanging around rather than abstracting them into a method or something.
Closes#13554.
This gives a better NOTE error message when a privacy error is encountered with
a static method. Previously no note was emitted (due to lack of support), but
now a note is emitted indicating that the struct/enum itself is private.
Closes#13641
This commit removes the compiler support for floating point modulus operations,
as well as from the language. An implementation for this operator is now
required to be provided by libraries.
Floating point modulus is rarely used, doesn't exist in C, and is always lowered
to an fmod library call by LLVM, and LLVM is considering removing support
entirely.
Closes#12278
