diff --git a/src/libcore/iter/range.rs b/src/libcore/iter/range.rs index 8d1080bb876ef..72b48b565719c 100644 --- a/src/libcore/iter/range.rs +++ b/src/libcore/iter/range.rs @@ -91,7 +91,7 @@ macro_rules! step_impl_unsigned { #[inline] #[allow(unreachable_patterns)] fn add_usize(&self, n: usize) -> Option { - match <$t>::try_from(n) { + match <$t>::private_try_from(n) { Ok(n_as_t) => self.checked_add(n_as_t), Err(_) => None, } @@ -123,7 +123,7 @@ macro_rules! step_impl_signed { #[inline] #[allow(unreachable_patterns)] fn add_usize(&self, n: usize) -> Option { - match <$unsigned>::try_from(n) { + match <$unsigned>::private_try_from(n) { Ok(n_as_unsigned) => { // Wrapping in unsigned space handles cases like // `-120_i8.add_usize(200) == Some(80_i8)`, @@ -461,3 +461,73 @@ impl DoubleEndedIterator for ops::RangeInclusive { #[stable(feature = "fused", since = "1.26.0")] impl FusedIterator for ops::RangeInclusive {} + +/// Compensate removal of some impls per +/// https://github.com/rust-lang/rust/pull/49305#issuecomment-376293243 +trait PrivateTryFromUsize: Sized { + fn private_try_from(n: usize) -> Result; +} + +impl PrivateTryFromUsize for T where T: TryFrom { + #[inline] + fn private_try_from(n: usize) -> Result { + T::try_from(n).map_err(|_| ()) + } +} + +// no possible bounds violation +macro_rules! try_from_unbounded { + ($($target:ty),*) => {$( + impl PrivateTryFromUsize for $target { + #[inline] + fn private_try_from(value: usize) -> Result { + Ok(value as $target) + } + } + )*} +} + +// unsigned to signed (only positive bound) +macro_rules! try_from_upper_bounded { + ($($target:ty),*) => {$( + impl PrivateTryFromUsize for $target { + #[inline] + fn private_try_from(u: usize) -> Result<$target, ()> { + if u > (<$target>::max_value() as usize) { + Err(()) + } else { + Ok(u as $target) + } + } + } + )*} +} + + +#[cfg(target_pointer_width = "16")] +mod ptr_try_from_impls { + use super::PrivateTryFromUsize; + + try_from_unbounded!(u16, u32, u64, u128); + try_from_unbounded!(i32, i64, i128); +} + +#[cfg(target_pointer_width = "32")] +mod ptr_try_from_impls { + use super::PrivateTryFromUsize; + + try_from_upper_bounded!(u16); + try_from_unbounded!(u32, u64, u128); + try_from_upper_bounded!(i32); + try_from_unbounded!(i64, i128); +} + +#[cfg(target_pointer_width = "64")] +mod ptr_try_from_impls { + use super::PrivateTryFromUsize; + + try_from_upper_bounded!(u16, u32); + try_from_unbounded!(u64, u128); + try_from_upper_bounded!(i32, i64); + try_from_unbounded!(i128); +} diff --git a/src/libcore/num/mod.rs b/src/libcore/num/mod.rs index 8f7e8d0c8ab78..ee041e1e4f1d9 100644 --- a/src/libcore/num/mod.rs +++ b/src/libcore/num/mod.rs @@ -3676,21 +3676,6 @@ impl From for TryFromIntError { } } -// no possible bounds violation -macro_rules! try_from_unbounded { - ($source:ty, $($target:ty),*) => {$( - #[stable(feature = "try_from", since = "1.26.0")] - impl TryFrom<$source> for $target { - type Error = TryFromIntError; - - #[inline] - fn try_from(value: $source) -> Result { - Ok(value as $target) - } - } - )*} -} - // only negative bounds macro_rules! try_from_lower_bounded { ($source:ty, $($target:ty),*) => {$( @@ -3789,27 +3774,20 @@ try_from_both_bounded!(i128, u64, u32, u16, u8); try_from_upper_bounded!(usize, isize); try_from_lower_bounded!(isize, usize); +try_from_upper_bounded!(usize, u8); +try_from_upper_bounded!(usize, i8, i16); +try_from_both_bounded!(isize, u8); +try_from_both_bounded!(isize, i8); + #[cfg(target_pointer_width = "16")] mod ptr_try_from_impls { use super::TryFromIntError; use convert::TryFrom; - try_from_upper_bounded!(usize, u8); - try_from_unbounded!(usize, u16, u32, u64, u128); - try_from_upper_bounded!(usize, i8, i16); - try_from_unbounded!(usize, i32, i64, i128); - - try_from_both_bounded!(isize, u8); + // Fallible across platfoms, only implementation differs try_from_lower_bounded!(isize, u16, u32, u64, u128); - try_from_both_bounded!(isize, i8); - try_from_unbounded!(isize, i16, i32, i64, i128); - - rev!(try_from_upper_bounded, usize, u32, u64, u128); rev!(try_from_lower_bounded, usize, i8, i16); rev!(try_from_both_bounded, usize, i32, i64, i128); - - rev!(try_from_upper_bounded, isize, u16, u32, u64, u128); - rev!(try_from_both_bounded, isize, i32, i64, i128); } #[cfg(target_pointer_width = "32")] @@ -3817,25 +3795,11 @@ mod ptr_try_from_impls { use super::TryFromIntError; use convert::TryFrom; - try_from_upper_bounded!(usize, u8, u16); - try_from_unbounded!(usize, u32, u64, u128); - try_from_upper_bounded!(usize, i8, i16, i32); - try_from_unbounded!(usize, i64, i128); - - try_from_both_bounded!(isize, u8, u16); + // Fallible across platfoms, only implementation differs + try_from_both_bounded!(isize, u16); try_from_lower_bounded!(isize, u32, u64, u128); - try_from_both_bounded!(isize, i8, i16); - try_from_unbounded!(isize, i32, i64, i128); - - rev!(try_from_unbounded, usize, u32); - rev!(try_from_upper_bounded, usize, u64, u128); rev!(try_from_lower_bounded, usize, i8, i16, i32); rev!(try_from_both_bounded, usize, i64, i128); - - rev!(try_from_unbounded, isize, u16); - rev!(try_from_upper_bounded, isize, u32, u64, u128); - rev!(try_from_unbounded, isize, i32); - rev!(try_from_both_bounded, isize, i64, i128); } #[cfg(target_pointer_width = "64")] @@ -3843,25 +3807,11 @@ mod ptr_try_from_impls { use super::TryFromIntError; use convert::TryFrom; - try_from_upper_bounded!(usize, u8, u16, u32); - try_from_unbounded!(usize, u64, u128); - try_from_upper_bounded!(usize, i8, i16, i32, i64); - try_from_unbounded!(usize, i128); - - try_from_both_bounded!(isize, u8, u16, u32); + // Fallible across platfoms, only implementation differs + try_from_both_bounded!(isize, u16, u32); try_from_lower_bounded!(isize, u64, u128); - try_from_both_bounded!(isize, i8, i16, i32); - try_from_unbounded!(isize, i64, i128); - - rev!(try_from_unbounded, usize, u32, u64); - rev!(try_from_upper_bounded, usize, u128); rev!(try_from_lower_bounded, usize, i8, i16, i32, i64); rev!(try_from_both_bounded, usize, i128); - - rev!(try_from_unbounded, isize, u16, u32); - rev!(try_from_upper_bounded, isize, u64, u128); - rev!(try_from_unbounded, isize, i32, i64); - rev!(try_from_both_bounded, isize, i128); } #[doc(hidden)] diff --git a/src/libcore/tests/num/mod.rs b/src/libcore/tests/num/mod.rs index 587dcbe6d6784..c7edb55b378c3 100644 --- a/src/libcore/tests/num/mod.rs +++ b/src/libcore/tests/num/mod.rs @@ -37,15 +37,6 @@ mod flt2dec; mod dec2flt; mod bignum; - -/// Adds the attribute to all items in the block. -macro_rules! cfg_block { - ($(#[$attr:meta]{$($it:item)*})*) => {$($( - #[$attr] - $it - )*)*} -} - /// Groups items that assume the pointer width is either 16/32/64, and has to be altered if /// support for larger/smaller pointer widths are added in the future. macro_rules! assume_usize_width { @@ -318,42 +309,6 @@ assume_usize_width! { test_impl_try_from_always_ok! { test_try_u16usize, u16, usize } test_impl_try_from_always_ok! { test_try_i16isize, i16, isize } - - test_impl_try_from_always_ok! { test_try_usizeu64, usize, u64 } - test_impl_try_from_always_ok! { test_try_usizeu128, usize, u128 } - test_impl_try_from_always_ok! { test_try_usizei128, usize, i128 } - - test_impl_try_from_always_ok! { test_try_isizei64, isize, i64 } - test_impl_try_from_always_ok! { test_try_isizei128, isize, i128 } - - cfg_block!( - #[cfg(target_pointer_width = "16")] { - test_impl_try_from_always_ok! { test_try_usizeu16, usize, u16 } - test_impl_try_from_always_ok! { test_try_isizei16, isize, i16 } - test_impl_try_from_always_ok! { test_try_usizeu32, usize, u32 } - test_impl_try_from_always_ok! { test_try_usizei32, usize, i32 } - test_impl_try_from_always_ok! { test_try_isizei32, isize, i32 } - test_impl_try_from_always_ok! { test_try_usizei64, usize, i64 } - } - - #[cfg(target_pointer_width = "32")] { - test_impl_try_from_always_ok! { test_try_u16isize, u16, isize } - test_impl_try_from_always_ok! { test_try_usizeu32, usize, u32 } - test_impl_try_from_always_ok! { test_try_isizei32, isize, i32 } - test_impl_try_from_always_ok! { test_try_u32usize, u32, usize } - test_impl_try_from_always_ok! { test_try_i32isize, i32, isize } - test_impl_try_from_always_ok! { test_try_usizei64, usize, i64 } - } - - #[cfg(target_pointer_width = "64")] { - test_impl_try_from_always_ok! { test_try_u16isize, u16, isize } - test_impl_try_from_always_ok! { test_try_u32usize, u32, usize } - test_impl_try_from_always_ok! { test_try_u32isize, u32, isize } - test_impl_try_from_always_ok! { test_try_i32isize, i32, isize } - test_impl_try_from_always_ok! { test_try_u64usize, u64, usize } - test_impl_try_from_always_ok! { test_try_i64isize, i64, isize } - } - ); } /// Conversions where max of $source can be represented as $target, @@ -402,24 +357,6 @@ assume_usize_width! { test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeu64, isize, u64 } test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeu128, isize, u128 } test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeusize, isize, usize } - - cfg_block!( - #[cfg(target_pointer_width = "16")] { - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeu16, isize, u16 } - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeu32, isize, u32 } - } - - #[cfg(target_pointer_width = "32")] { - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_isizeu32, isize, u32 } - - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_i32usize, i32, usize } - } - - #[cfg(target_pointer_width = "64")] { - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_i32usize, i32, usize } - test_impl_try_from_signed_to_unsigned_upper_ok! { test_try_i64usize, i64, usize } - } - ); } /// Conversions where max of $source can not be represented as $target, @@ -461,29 +398,9 @@ test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u128i64, u128, i64 } test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u128i128, u128, i128 } assume_usize_width! { - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u64isize, u64, isize } - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u128isize, u128, isize } - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizei8, usize, i8 } test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizei16, usize, i16 } test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizeisize, usize, isize } - - cfg_block!( - #[cfg(target_pointer_width = "16")] { - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u16isize, u16, isize } - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u32isize, u32, isize } - } - - #[cfg(target_pointer_width = "32")] { - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_u32isize, u32, isize } - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizei32, usize, i32 } - } - - #[cfg(target_pointer_width = "64")] { - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizei32, usize, i32 } - test_impl_try_from_unsigned_to_signed_upper_err! { test_try_usizei64, usize, i64 } - } - ); } /// Conversions where min/max of $source can not be represented as $target. @@ -543,34 +460,6 @@ test_impl_try_from_same_sign_err! { test_try_i128i64, i128, i64 } assume_usize_width! { test_impl_try_from_same_sign_err! { test_try_usizeu8, usize, u8 } - test_impl_try_from_same_sign_err! { test_try_u128usize, u128, usize } - test_impl_try_from_same_sign_err! { test_try_i128isize, i128, isize } - - cfg_block!( - #[cfg(target_pointer_width = "16")] { - test_impl_try_from_same_sign_err! { test_try_u32usize, u32, usize } - test_impl_try_from_same_sign_err! { test_try_u64usize, u64, usize } - - test_impl_try_from_same_sign_err! { test_try_i32isize, i32, isize } - test_impl_try_from_same_sign_err! { test_try_i64isize, i64, isize } - } - - #[cfg(target_pointer_width = "32")] { - test_impl_try_from_same_sign_err! { test_try_u64usize, u64, usize } - test_impl_try_from_same_sign_err! { test_try_usizeu16, usize, u16 } - - test_impl_try_from_same_sign_err! { test_try_i64isize, i64, isize } - test_impl_try_from_same_sign_err! { test_try_isizei16, isize, i16 } - } - - #[cfg(target_pointer_width = "64")] { - test_impl_try_from_same_sign_err! { test_try_usizeu16, usize, u16 } - test_impl_try_from_same_sign_err! { test_try_usizeu32, usize, u32 } - - test_impl_try_from_same_sign_err! { test_try_isizei16, isize, i16 } - test_impl_try_from_same_sign_err! { test_try_isizei32, isize, i32 } - } - ); } /// Conversions where neither the min nor the max of $source can be represented by @@ -615,22 +504,6 @@ test_impl_try_from_signed_to_unsigned_err! { test_try_i128u64, i128, u64 } assume_usize_width! { test_impl_try_from_signed_to_unsigned_err! { test_try_isizeu8, isize, u8 } test_impl_try_from_signed_to_unsigned_err! { test_try_i128usize, i128, usize } - - cfg_block! { - #[cfg(target_pointer_width = "16")] { - test_impl_try_from_signed_to_unsigned_err! { test_try_i32usize, i32, usize } - test_impl_try_from_signed_to_unsigned_err! { test_try_i64usize, i64, usize } - } - #[cfg(target_pointer_width = "32")] { - test_impl_try_from_signed_to_unsigned_err! { test_try_i64usize, i64, usize } - - test_impl_try_from_signed_to_unsigned_err! { test_try_isizeu16, isize, u16 } - } - #[cfg(target_pointer_width = "64")] { - test_impl_try_from_signed_to_unsigned_err! { test_try_isizeu16, isize, u16 } - test_impl_try_from_signed_to_unsigned_err! { test_try_isizeu32, isize, u32 } - } - } } macro_rules! test_float { diff --git a/src/libstd/io/cursor.rs b/src/libstd/io/cursor.rs index 76bcb5fedc94a..2673f3ccfa3ab 100644 --- a/src/libstd/io/cursor.rs +++ b/src/libstd/io/cursor.rs @@ -10,7 +10,6 @@ use io::prelude::*; -use core::convert::TryInto; use cmp; use io::{self, Initializer, SeekFrom, Error, ErrorKind}; @@ -260,9 +259,26 @@ fn slice_write(pos_mut: &mut u64, slice: &mut [u8], buf: &[u8]) -> io::Result Result { + if n <= (::max_value() as u64) { + Ok(n as usize) + } else { + Err(()) + } +} + +#[cfg(any(target_pointer_width = "64"))] +fn try_into(n: u64) -> Result { + Ok(n as usize) +} + // Resizing write implementation fn vec_write(pos_mut: &mut u64, vec: &mut Vec, buf: &[u8]) -> io::Result { - let pos: usize = (*pos_mut).try_into().map_err(|_| { + let pos: usize = try_into(*pos_mut).map_err(|_| { Error::new(ErrorKind::InvalidInput, "cursor position exceeds maximum possible vector length") })?;