Display `\t` in diagnostics code as four spaces
Follow up to #44386 using the unicode variable width machinery from #45711 to replace tabs in the source code when displaying a diagnostic error with four spaces (instead of only one), while properly accounting for this when calculating underlines.
Partly addresses #44618.
Fixes#38384
Most of the Rust community uses 4 spaces for indentation,
but there are also tab users of Rust (including myself!).
This patch fixes a bug in error printing which mispositions
error indicators when near code with tabs.
The code attempted to fix the issue by replacing spaces
with tabs, but it sadly wasn't enough, as sometimes
you may not print spaces but _ or ^ instead.
This patch employs the reverse strategy: it replaces each
tab with a space, so that the number of _ and ^ and spaces
in error indicators below the code snippet line up
perfectly.
In a study [1] preceeding this patch, we could see that
this strategy is also chosen by gcc version 6.3.0.
Its not perfect, as the output is not beautiful, but its
the easiest to implement. If anyone wants to improve on
this, be my guest! This patch is meant as improvement of
the status quo, not as perfect end status. It fixes the
actual issue of mispositioning error indicators.
[1]: https://github.com/rust-lang/rust/issues/38384#issuecomment-326813710
add thiscall calling convention support
This support is needed for bindgen to work well on 32-bit Windows, and also enables people to begin experimenting with C++ FFI support on that platform.
Fixes#42044.
This support is needed for bindgen to work well on 32-bit Windows, and
also enables people to begin experimenting with C++ FFI support on that
platform.
Fixes#42044.
This converts all of borrowck's `mut` suggestions to a new
`mc::ImmutabilityBlame` API instead of the current mix of various hacks.
Fixes#35937.
Fixes#40823.
Tracking issue: https://github.com/rust-lang/rust/issues/40180
This calling convention can be used for definining interrupt handlers on
32-bit and 64-bit x86 targets. The compiler then uses `iret` instead of
`ret` for returning and ensures that all registers are restored to their
original values.
Usage:
```
extern "x86-interrupt" fn handler(stack_frame: &ExceptionStackFrame) {…}
```
for interrupts and exceptions without error code and
```
extern "x86-interrupt" fn page_fault_handler(stack_frame: &ExceptionStackFrame,
error_code: u64) {…}
```
for exceptions that push an error code (e.g., page faults or general
protection faults). The programmer must ensure that the correct version
is used for each interrupt.
For more details see the [LLVM PR][1] and the corresponding [proposal][2].
[1]: https://reviews.llvm.org/D15567
[2]: http://lists.llvm.org/pipermail/cfe-dev/2015-September/045171.html
Given the following code:
```rust
struct Foo<T: Clone>(T);
use std::ops::Add;
impl<T: Clone, Add> Add for Foo<T> {
type Output = usize;
fn add(self, rhs: Self) -> Self::Output {
unimplemented!();
}
}
```
present the following output:
```nocode
error[E0404]: `Add` is not a trait
--> file3.rs:5:21
|
5 | impl<T: Clone, Add> Add for Okok<T> {
| --- ^^^ expected trait, found type parameter
| |
| type parameter defined here
```
