Remove alternate stack with sigaltstack before unmaping it.
Also reuse existing signal stack if already set, this is especially
useful when working with sanitizers that configure alternate stack
themselves.
This change depends on SS_DISABLE recently introduced in libc crate and updates
this git submodule accordingly.
Previously the docs suggested that '❤️' doesn't fit in a char because
it's 6 bytes. But that's misleading. 'a̚' also doesn't fit in a char,
even though it's only 3 bytes. The important thing is the number of code
points, not the number of bytes. Clarify the primitive char docs around
this.
The first time I read the docs for `insert()`, I thought it was saying it didn't update existing *values*, and I was confused. Reword the docs to make it clear that `insert()` does update values.
Because we no longer use `GetFileAttributesExW` FileAttr is never created directly from `WIN32_FILE_ATTRIBUTE_DATA` anymore. So we should no longer store FileAttr's attributes in that c struct.
r? @alexcrichton
Is this what you had in mind?
This follows the pattern already used for stat functions from #31551. Now
`ftruncate`, `lseek`, and `readdir_r` use their explicit 64-bit variants for
LFS support, using wider `off_t` and `dirent` types. This also updates to
`open64`, which uses no different types but implies the `O_LARGEFILE` flag.
Non-Linux platforms just map their normal functions to the 64-bit names.
r? @alexcrichton
The first time I read the docs for `insert()`, I thought it was saying
it didn't update existing *values*, and I was confused. Reword the docs
to make it clear that `insert()` does update values.
Previously the docs suggested that '❤️' doesn't fit in a char because
it's 6 bytes. But that's misleading. 'a̚' also doesn't fit in a char,
even though it's only 3 bytes. The important thing is the number of code
points, not the number of bytes. Clarify the primitive char docs around
this.
Because we no longer use `GetFileAttributesExW` FileAttr is never created
directly from `WIN32_FILE_ATTRIBUTE_DATA` anymore.
So we should no longer store FileAttr's attributes in that c struct.
This commit is an implementation of [RFC 1415][rfc] which deprecates all types
in the `std::os::*::raw` modules.
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1415-trim-std-os.md
Many of the types in these modules don't actually have a canonical platform
representation, for example the definition of `stat` on 32-bit Linux will change
depending on whether C code is compiled with LFS support or not. Unfortunately
the current types in `std::os::*::raw` are billed as "compatible with C", which
in light of this means it isn't really possible.
To make matters worse, platforms like Android sometimes define these types as
*smaller* than the way they're actually represented in the `stat` structure
itself. This means that when methods like `DirEntry::ino` are called on Android
the result may be truncated as we're tied to returning a `ino_t` type, not the
underlying type.
The commit here incorporates two backwards-compatible components:
* Deprecate all `raw` types that aren't in `std::os::raw`
* Expand the `std::os::*::fs::MetadataExt` trait on all platforms for method
accessors of all fields. The fields now returned widened types which are the
same across platforms (consistency across platforms is not required, however,
it's just convenient).
and two also backwards-incompatible components:
* Change the definition of all `std::os::*::raw` type aliases to
correspond to the newly widened types that are being returned on each
platform.
* Change the definition of `std::os::*::raw::stat` on Linux to match the LFS
definitions rather than the standard ones.
The breaking changes here will specifically break code that assumes that `libc`
and `std` agree on the definition of `std::os::*::raw` types, or that the `std`
types are faithful representations of the types in C. An [audit] has been
performed of crates.io to determine the fallout which was determined two be
minimal, with the two found cases of breakage having been fixed now.
[audit]: https://github.com/rust-lang/rfcs/pull/1415#issuecomment-180645582
---
Ok, so after all that, we're finally able to support LFS on Linux! This commit
then simultaneously starts using `stat64` and friends on Linux to ensure that we
can open >4GB files on 32-bit Linux. Yay!
Closes#28978Closes#30050Closes#31549
This commit is an implementation of [RFC 1415][rfc] which deprecates all types
in the `std::os::*::raw` modules.
[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1415-trim-std-os.md
Many of the types in these modules don't actually have a canonical platform
representation, for example the definition of `stat` on 32-bit Linux will change
depending on whether C code is compiled with LFS support or not. Unfortunately
the current types in `std::os::*::raw` are billed as "compatible with C", which
in light of this means it isn't really possible.
To make matters worse, platforms like Android sometimes define these types as
*smaller* than the way they're actually represented in the `stat` structure
itself. This means that when methods like `DirEntry::ino` are called on Android
the result may be truncated as we're tied to returning a `ino_t` type, not the
underlying type.
The commit here incorporates two backwards-compatible components:
* Deprecate all `raw` types that aren't in `std::os::raw`
* Expand the `std::os::*::fs::MetadataExt` trait on all platforms for method
accessors of all fields. The fields now returned widened types which are the
same across platforms (consistency across platforms is not required, however,
it's just convenient).
and two also backwards-incompatible components:
* Change the definition of all `std::os::*::raw` type aliases to
correspond to the newly widened types that are being returned on each
platform.
* Change the definition of `std::os::*::raw::stat` on Linux to match the LFS
definitions rather than the standard ones.
The breaking changes here will specifically break code that assumes that `libc`
and `std` agree on the definition of `std::os::*::raw` types, or that the `std`
types are faithful representations of the types in C. An [audit] has been
performed of crates.io to determine the fallout which was determined two be
minimal, with the two found cases of breakage having been fixed now.
[audit]: https://github.com/rust-lang/rfcs/pull/1415#issuecomment-180645582
---
Ok, so after all that, we're finally able to support LFS on Linux! This commit
then simultaneously starts using `stat64` and friends on Linux to ensure that we
can open >4GB files on 32-bit Linux. Yay!
Closes#28978Closes#30050Closes#31549
Fix `read_link` to also be able to read the target of junctions on Windows.
Also the path returned should not include a NT namespace, and there were
some problems with permissions.
This series of commits adds the initial implementation of a new build system for
the compiler and standard library based on Cargo. The high-level architecture
now looks like:
1. The `./configure` script is run with `--enable-rustbuild` and other standard
configuration options.
2. A `Makefile` is generate which proxies commands to the new build system.
3. The new build system has a Python script entry point which manages
downloading both a Rust and Cargo nightly. This initial script also manages
building the build system itself (which is written in Rust).
4. The build system, written in rust and called `bootstrap`, architects how to
call `cargo` and manages building all native libraries and such.
One might reasonably ask "why rewrite the build system?", which is a good
question! The Rust project has used Makefiles for as long as I can remember at
least, and while ugly and difficult to use are undeniably robust as they contain
years worth of tweaking and tuning for working on as many platforms in as many
situation as possible. The rationale behind this PR, however is:
* The makefiles are impenetrable to all but a few people on this
planet. This means that contributions to the build system are almost
nonexistent, and furthermore if a build system change is needed it's
incredibly difficult to figure out how to do so. This hindrance prevents us
from doing some "perhaps fancier" things we may wish to do in make.
* Our build system, while portable, is unfortunately not infinitely portable
everywhere. For example the recently-introduced MSVC target is quite unlikely
to have `make` installed by default (e.g. it requires building inside of an
MSYS2 shell currently). Conversely, the portability of make comes at a cost of
crazy and weird hacks to work around all sorts of versions of software
everywhere, especially when it comes to the configure script and makefiles.
By rewriting this logic in one of the most robust platforms there is, Rust,
we get to assuage all of these worries for free!
* There's a standard tool to build Rust crates, Cargo, but the standard library
and compiler don't use it. This means that they cannot benefit easily from the
crates.io ecosystem, nor can the ecosystem benefit from a standard way to
build this repository itself. Moving to Cargo should help assuage both of
these needs. This has the added benefit of making the compiler more
approachable for newbies as working on the compiler will just happen to be
working on a large Cargo project, all the same standard tools and tricks will
apply.
* There's a huge amount of portability information in the main distribution, for
example around cross compiling, compiling on new OSes, etc. Pushing this logic
into standard crates (like `gcc`) enables the community to immediately benefit
from new build logic.
Despite these benefits, it's going to be a long road to actually replace our
current build system. This PR is just the beginning and doesn't implement the
full suite of functionality as the current one, but there are many more to
follow! The current implementation strategy hopes to look like:
1. Land a second build system in-tree that can be itereated on an and
contributed to. This will not be used just yet in terms of gating new commits
to the repo.
2. Over time, bring the second build system to feature parity with the old build
system, start setting up CI for both build systems.
3. At some point in the future, switch the default to the new build system, but
keep the old one around.
4. At some further point in the future, delete the entire old build system.
---
Alright, so with all that out of the way, here's some more info on this PR
itself. The inital build system here is contained in the `src/bootstrap`
directory and just adds the necessary minimum bits to bootstrap the compiler
itself. There is currently no support for building documentation, running tests,
or installing, but the implemented support is:
* Compiling LLVM with `cmake` instead of `./configure` + `make`. The LLVM
project is removing their autotools build system, so we'd have to make this
transition eventually anyway.
* Compiling compiler-rt with `cmake` as well (for the same rationale as above).
* Adding `Cargo.toml` to map out the dependency graph to all crates, and also
adding `build.rs` files where appropriate. For example `alloc_jemalloc` has a
script to build jemalloc, `flate` has a script to build `miniz.c`, `std` will
build `libbacktrace`, etc.
* Orchestrating all the calls to `cargo` to build the standard distribution,
following the normal bootstrapping process. This also tracks dependencies
between steps to ensure cross-compilation targets happen as well.
* Configuration is intended to eventually be done through a `config.toml` file,
so support is implemented for this. The most likely vector of configuration
for now, however, is likely through `config.mk` (what `./configure` emits), so
the build system currently parses this information.
There's still quite a few steps left to do, and I'll open up some follow-up
issues (as well as a tracking issue) for this migration, but hopefully this is a
great start to get going! This PR is currently tested on all the
Windows/Linux/OSX triples for x86\_64 and x86, but more portability is always
welcome!
---
Future functionality left to implement
* [ ] Re-verify that multi-host builds work
* [ ] Verify android build works
* [ ] Verify iOS build work (mostly compiler-rt)
* [ ] Verify sha256 and ideally gpg of downloaded nightly compiler and nightly rustc
* [ ] Implement testing -- this is a huge bullet point with lots of sub-bullets
* [ ] Build and generate documentation (plus the various tools we have in-tree)
* [ ] Move various src/etc scripts into Rust -- not sure how this interacts with `make` build system
* [ ] Implement `make install` - like testing this is also quite massive
* [x] Deduplicate version information with makefiles
