Add tier 3 no_std x86 support for QNX Neutrino RTOS, version 7.0
This PR adds the target `i586-pc-nto-qnx700`, which targets QNX Neutrino RTOS version 7.0 on x86 32-bit targets.
cc: `@flba-eb` `@gh-tr`
This target falls under the umbrella of Tier 3 QNX Neutrino RTOS support documented in `nto-qnx.md` and previously started with #102701.
Switch to LLD as default linker for {arm,thumb}v4t-none-eabi
The LLVM 16 update brought ARMv4t support to LLD. We should use it by default so users don't need to install an external linker.
cc `@Lokathor`
`-Cdebuginfo=1` was never line tables only and
can't be due to backwards compatibility issues.
This was clarified and an option for line tables only
was added. Additionally an option for line info
directives only was added, which is well needed for
some targets. The debug info options should now
behave the same as clang's debug info options.
rustdoc: add support for type filters in arguments and generics
This makes sense, since the search index has the information in it, and it's more useful for function signature searches since a function signature search's item type is, by definition, some type of function (there's more than one, but not very many).
Support for Fuchsia RISC-V target
Fuchsia is in the process of implementing the RISC-V support. This change implements the minimal Rust compiler support. The support for building runtime libraries will be implemented in follow up changes once Fuchsia SDK has the RISC-V support.
Remove `box_syntax`
r? `@Nilstrieb`
This removes the feature `box_syntax`, which allows the use of `box <expr>` to create a Box, and finalises removing use of the feature from the compiler. `box_patterns` (allowing the use of `box <pat>` in a pattern) is unaffected.
It also removes `ast::ExprKind::Box` - the only way to create a 'box' expression now is with the rustc-internal `#[rustc_box]` attribute.
As a temporary measure to help users move away, `box <expr>` now parses the inner expression, and emits a `MachineApplicable` lint to replace it with `Box::new`
Closes#49733
Remove `llvm.skip-rebuild` option
This was added to in 2019 to speed up rebuild times when LLVM was modified. Now that download-ci-llvm exists, I don't think it makes sense to support an unsound option like this that can lead to miscompiles; and the code cleanup is nice too.
r? `@Mark-Simulacrum` cc `@varkor` #65612
Fuchsia is in the process of implementing the RISC-V support. This
change implements the minimal Rust compiler support. The support for
building runtime libraries will be implemented in follow up changes
once Fuchsia SDK has the RISC-V support.
add -Zexport-executable-symbols to unstable book
This flag has been extremely useful to me, but it's hard to discover. The text contains a bunch of terms that hopefully a search engine will pick up on when someone searches for this functionality.
Add support for QNX Neutrino to standard library
This change:
- adds standard library support for QNX Neutrino (7.1).
- upgrades `libc` to version `0.2.139` which supports QNX Neutrino
`@gh-tr`
⚠️ Backtraces on QNX require https://github.com/rust-lang/backtrace-rs/pull/507 which is not yet merged! (But everything else works without these changes) ⚠️
Tested mainly with a x86_64 virtual machine (see qnx-nto.md) and partially with an aarch64 hardware (some tests fail due to constrained resources).
