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Remove (fn(...) -> ...) -> usize -> *const () -> usize cast

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This commit is contained in:
Maybe Waffle 2022-05-26 13:30:27 +04:00
parent b2eba058e6
commit ac5c15d6be
2 changed files with 36 additions and 40 deletions
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62
library/core/src/fmt/mod.rs
View file

@ -2233,37 +2233,43 @@ impl Display for char {
#[stable(feature = "rust1", since = "1.0.0")]
impl<T: ?Sized> Pointer for *const T {
fn fmt(&self, f: &mut Formatter<'_>) -> Result {
/// Since the formatting will be identical for all pointer types, use a non-monomorphized
/// implementation for the actual formatting to reduce the amount of codegen work needed
fn inner(ptr: *const (), f: &mut Formatter<'_>) -> Result {
let old_width = f.width;
let old_flags = f.flags;
// The alternate flag is already treated by LowerHex as being special-
// it denotes whether to prefix with 0x. We use it to work out whether
// or not to zero extend, and then unconditionally set it to get the
// prefix.
if f.alternate() {
f.flags |= 1 << (FlagV1::SignAwareZeroPad as u32);
if f.width.is_none() {
f.width = Some((usize::BITS / 4) as usize + 2);
}
}
f.flags |= 1 << (FlagV1::Alternate as u32);
let ret = LowerHex::fmt(&(ptr.addr()), f);
f.width = old_width;
f.flags = old_flags;
ret
}
inner(*self as *const (), f)
// Cast is needed here because `.addr()` requires `T: Sized`.
pointer_fmt_inner((*self as *const ()).addr(), f)
}
}
/// Since the formatting will be identical for all pointer types, use a non-monomorphized
/// implementation for the actual formatting to reduce the amount of codegen work needed.
///
/// This uses `ptr_addr: usize` and not `ptr: *const ()` to be able to use this for
/// `fn(...) -> ...` without using [problematic] "Oxford Casts".
///
/// [problematic]: https://github.com/rust-lang/rust/issues/95489
pub(crate) fn pointer_fmt_inner(ptr_addr: usize, f: &mut Formatter<'_>) -> Result {
let old_width = f.width;
let old_flags = f.flags;
// The alternate flag is already treated by LowerHex as being special-
// it denotes whether to prefix with 0x. We use it to work out whether
// or not to zero extend, and then unconditionally set it to get the
// prefix.
if f.alternate() {
f.flags |= 1 << (FlagV1::SignAwareZeroPad as u32);
if f.width.is_none() {
f.width = Some((usize::BITS / 4) as usize + 2);
}
}
f.flags |= 1 << (FlagV1::Alternate as u32);
let ret = LowerHex::fmt(&ptr_addr, f);
f.width = old_width;
f.flags = old_flags;
ret
}
#[stable(feature = "rust1", since = "1.0.0")]
impl<T: ?Sized> Pointer for *mut T {
fn fmt(&self, f: &mut Formatter<'_>) -> Result {

14
library/core/src/ptr/mod.rs
View file

@ -1831,24 +1831,14 @@ macro_rules! fnptr_impls_safety_abi {
#[stable(feature = "fnptr_impls", since = "1.4.0")]
impl<Ret, $($Arg),*> fmt::Pointer for $FnTy {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
// HACK: The intermediate cast as usize is required for AVR
// so that the address space of the source function pointer
// is preserved in the final function pointer.
//
// https://github.com/avr-rust/rust/issues/143
fmt::Pointer::fmt(&(*self as usize as *const ()), f)
fmt::pointer_fmt_inner(*self as usize, f)
}
}
#[stable(feature = "fnptr_impls", since = "1.4.0")]
impl<Ret, $($Arg),*> fmt::Debug for $FnTy {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
// HACK: The intermediate cast as usize is required for AVR
// so that the address space of the source function pointer
// is preserved in the final function pointer.
//
// https://github.com/avr-rust/rust/issues/143
fmt::Pointer::fmt(&(*self as usize as *const ()), f)
fmt::pointer_fmt_inner(*self as usize, f)
}
}
}