Use f{32,64}::to_bits for is_zero test in vec::SpecFromElem
vec::SpecFromElem provides an optimization to use calloc to fill a Vec
when the element given to fill the Vec is represented by 0.
For floats, the test for that currently used is `x == 0. &&
x.is_sign_positive()`. When compiled in a standalone function, rustc
generates the following assembly:
```
xorps xmm1, xmm1
ucomisd xmm0, xmm1
setnp al
sete cl
and cl, al
movq rax, xmm0
test rax, rax
setns al
and al, cl
ret
```
A simpler test telling us whether the value is represented by 0, is
`x.to_bits() == 0`, which rustc compiles to:
```
movq rax, xmm0
test rax, rax
sete al
ret
```
Not that the test is hot in any way, but it also makes it clearer what
the intent in the rust code is.
rustbuild: Don't leak file handles when creating junctions on Windows
This fixes building the compiler docs because stage1-rustc\x86_64-pc-windows-msvc\doc is used twice which doesn't work if we still have a handle from the first time.
rustc: Group linked libraries where needed
This commit fixes a longstanding issue with the compiler with circular
dependencies between libcore and libstd. The `core` crate requires at least one
symbol, the ability to unwind. The `std` crate is the crate which actually
defines this symbol, but the `std` crate also depends on the `core` crate.
This circular dependency is in general disallowed in Rust as crates cannot have
cycles amongst them. A special exception is made just for core/std, but this is
also unfortunately incompatible with how GNU linkers work. GNU linkers will
process undefined symbols in a left-to-right fashion, only actually linking an
rlib like libstd if there are any symbols used from it. This strategy is
incompatible with circular dependencies because if we otherwise don't use
symbols from libstd we don't discover that we needed it until we're later
processing libcore's symbols!
To fix this GNU linkers support the `--start-group` and `--end-group` options
which indicate "libraries between these markers may have circular dependencies
amongst them. The linker invocation has been updated to automatically pass these
arguments when we're invoking a GNU linker and automatically calculate where the
arguments need to go (around libstd and libcore)
Closes#18807Closes#47074
This commit fixes a longstanding issue with the compiler with circular
dependencies between libcore and libstd. The `core` crate requires at least one
symbol, the ability to unwind. The `std` crate is the crate which actually
defines this symbol, but the `std` crate also depends on the `core` crate.
This circular dependency is in general disallowed in Rust as crates cannot have
cycles amongst them. A special exception is made just for core/std, but this is
also unfortunately incompatible with how GNU linkers work. GNU linkers will
process undefined symbols in a left-to-right fashion, only actually linking an
rlib like libstd if there are any symbols used from it. This strategy is
incompatible with circular dependencies because if we otherwise don't use
symbols from libstd we don't discover that we needed it until we're later
processing libcore's symbols!
To fix this GNU linkers support the `--start-group` and `--end-group` options
which indicate "libraries between these markers may have circular dependencies
amongst them. The linker invocation has been updated to automatically pass these
arguments when we're invoking a GNU linker and automatically calculate where the
arguments need to go (around libstd and libcore)
Closes#18807Closes#47074
Rename RangeArgument to RangeBounds, move it and Bound to libcore
As proposed in the tracking issue: https://github.com/rust-lang/rust/issues/30877
Changes to *stable* items:
* `core::ops::Bound` / `std::ops::Bound` is new
* `std::collections::Bound` is a deprecated reexport of it (does this actually cause a warning?)
Changes to *unstable* items
* `alloc::Bound` is gone
* `alloc::range::RangeArgument` is moved to `core::ops::RangeBounds` / `std::ops::RangeBounds`
* `alloc::range` is gone
* `std::collections::range::RangeArgument` is deprecated reexport, to be removed later
* `std::collections::range` is deprecated, to be removed later
* `impl RangeBounds<T> for Range{,From,To,Inclusive,ToInclusive}<&T>` are added
The idea of replacing this trait with a type to be used with `Into<_>` is left for future consideration / work.
(Fixes https://github.com/rust-lang-nursery/rust-clippy/issues/2552.)
When a module is declared, but no matching file exists, rustc gives
an error like 'help: name the file either foo.rs or foo/mod.rs inside
the directory "src/bar"'. However, at on windows, the backslash was
double-escaped when naming the directory.
It did this because the string was printed in debug mode ( "{:?}" ) to
surround it with quotes. However, it should just be printed like any
other directory in an error message and surrounded by escaped quotes,
rather than relying on the debug print to add quotes ( "\"{}\"" ).
Update Cargo
This includes https://github.com/rust-lang/cargo/pull/5255 which fixed regression in `cargo rustdoc` command.
If beta branches before this is merged, we'll need to backport as well
Remove universes from `ty::ParamEnv`
This change was never meant to land. #48407 takes an alternate approach. However, that PR is now blocked on some issues with canonicalization, and rebasing these reverts gets harder each time, so let's just get this bit out of the way now.
r? @nikomatsakis
Check for known but incorrect attributes
fixes#43988
- Change nested_visit_map so it will recursively check functions
- Add visit_stmt and visit_expr for impl Visitor for CheckAttrVisitor and check for incorrect
inline and repr attributes on staements and expressions
- Add regression test for issue #43988
vec::SpecFromElem provides an optimization to use calloc to fill a Vec
when the element given to fill the Vec is represented by 0.
For floats, the test for that currently used is `x == 0. &&
x.is_sign_positive()`. When compiled in a standalone function, rustc
generates the following assembly:
```
xorps xmm1, xmm1
ucomisd xmm0, xmm1
setnp al
sete cl
and cl, al
movq rax, xmm0
test rax, rax
setns al
and al, cl
ret
```
A simpler test telling us whether the value is represented by 0, is
`x.to_bits() == 0`, which rustc compiles to:
```
movq rax, xmm0
test rax, rax
sete al
ret
```
Not that the test is hot in any way, but it also makes it clearer what
the intent in the rust code is.
This fixes building the compiler docs because stage1-rustc\x86_64-pc-windows-msvc\doc is used twice which
doesn't work if we still have a handle from the first time.
