Use hints with getaddrinfo() in std::net::lookup_host()
As noted in #24250, `std::net::lookup_host()` repeats each IPv[46] address in the result set. The number of repetitions is OS-dependent; e.g., Linux and FreeBSD give three copies, OpenBSD gives two. Filtering the duplicates can be done by the user if `lookup_host()` is used explicitly, but not with functions like `TcpStream::connect()`. What happens with the latter is that any unsuccessful connection attempt will be repeated as many times as there are duplicates of the address.
The program:
```rust
use std::net::TcpStream;
fn main() {
let _stream = TcpStream::connect("localhost:4444").unwrap();
}
```
results in the following capture:
[capture-before.txt](https://github.com/rust-lang/rust/files/352004/capture-before.txt)
assuming that "localhost" resolves both to ::1 and 127.0.0.1, and that the listening program opens just an IPv4 socket (e.g., `nc -l 127.0.0.1 4444`.) The reason for this behavior is explained in [this comment](https://github.com/rust-lang/rust/issues/24250#issuecomment-92240152): `getaddrinfo()` is not constrained.
Various OSS projects (I checked out Postfix, OpenLDAP, Apache HTTPD and BIND) which use `getaddrinfo()` generally constrain the result set by using a non-NULL `hints` parameter and setting at least `ai_socktype` to `SOCK_STREAM`. `SOCK_DGRAM` would also work. Other parameters are unnecessary for pure name resolution.
The patch in this PR initializes a `hints` struct and passes it to `getaddrinfo()`, which eliminates the duplicates. The same test program as above with this change produces:
[capture-after.txt](https://github.com/rust-lang/rust/files/352042/capture-after.txt)
All `libstd` tests pass with this patch.
Clarify rustbuild + msvc + vcvars in README
The invocation of vcvars is only needed for versions of Visual Studio that
rustbuild or cmake doesn't understand, but if older versions are installed then
there's no need to call vcvars.
Closes#34576
Drive trans from the output of the translation item collector
This PR changes the way how translation works above the item level. Instead of walking the HIR and calling `trans_item()` on everything encountered (while instantiating monomorphizations on-demand), we now just process the list of translation items generated by the `trans::collector`. Using the collector has the benefit of being able to know the exact set of monomorphizations and symbols before actually running translation, something that is crucial for incremental compilation (but also has [other benefits](https://github.com/rust-lang/rust/pull/33602)).
The collector has existed for quite a while now, but so far it's output was only used for running some auto-tests. With this PR it becomes the only source of truth about what gets translated.
One modification we had to make, compared to the initial approach, is that closures are not represented as their own `TransItems`. Doing so, while still supporting non-MIR-based translation, would have been prohibitively complex, and not worth the trouble since legacy-trans will disappear sooner or later. Once there is solely MIR-trans, it would be a good idea to make closures `TransItems` again.
This PR removes the most obvious functions and tables that are not needed anymore, but there's definitely still more cleanup possible later on (e.g. `monomorphize::monomorphic_fn()` does very little at this point). Since there are already more than 10 commits in here, doing this in a separate PR seems to be a better idea.
These changes definitely warrant a crater run.
Thanks @Aatch, for taking on one of the more tedious tasks during the dev-sprint!
Thanks @eddyb, for doing some nice refactorings to symbol name generation and making sure these landed so I could use them!
cc @rust-lang/compiler
cc @rust-lang/tools
The data tracked here was meant to compare the output of the
translation item collector to the set of translation items found
by the on-demand translator.
Functions and method are declared ahead-of-time, including generic ones.
Closures are not considered trans items anymore, instead they are
translated on demands.
Update definitions in def_map for associated types written in unqualified form (like `Self::Output`)
Cleanup finish_resolving_def_to_ty/resolve_ty_and_def_ufcs
Make VariantDef's available through constructor IDs
Use hints with getaddrinfo() in std::net::lookup_host()
As noted in #24250, `std::net::lookup_host()` repeats each IPv[46] address in the result set. The number of repetitions is OS-dependent; e.g., Linux and FreeBSD give three copies, OpenBSD gives two. Filtering the duplicates can be done by the user if `lookup_host()` is used explicitly, but not with functions like `TcpStream::connect()`. What happens with the latter is that any unsuccessful connection attempt will be repeated as many times as there are duplicates of the address.
The program:
```rust
use std::net::TcpStream;
fn main() {
let _stream = TcpStream::connect("localhost:4444").unwrap();
}
```
results in the following capture:
[capture-before.txt](https://github.com/rust-lang/rust/files/352004/capture-before.txt)
assuming that "localhost" resolves both to ::1 and 127.0.0.1, and that the listening program opens just an IPv4 socket (e.g., `nc -l 127.0.0.1 4444`.) The reason for this behavior is explained in [this comment](https://github.com/rust-lang/rust/issues/24250#issuecomment-92240152): `getaddrinfo()` is not constrained.
Various OSS projects (I checked out Postfix, OpenLDAP, Apache HTTPD and BIND) which use `getaddrinfo()` generally constrain the result set by using a non-NULL `hints` parameter and setting at least `ai_socktype` to `SOCK_STREAM`. `SOCK_DGRAM` would also work. Other parameters are unnecessary for pure name resolution.
The patch in this PR initializes a `hints` struct and passes it to `getaddrinfo()`, which eliminates the duplicates. The same test program as above with this change produces:
[capture-after.txt](https://github.com/rust-lang/rust/files/352042/capture-after.txt)
All `libstd` tests pass with this patch.
enhancewindows documentation in getting-started
- minor pronoun fix We -> You
- PATH troubleshooting
- dir output is vertical (but did not include timestamps)
- executables not in %PATH% require .\
r? @steveklabnik
Correct inline assembly clobber formatting.
Fixes the formatting for inline assembly clobbers used in the book.
As this causes llvm to silently ignore the clobber an error is also
added to catch cases in which the wrong formatting was used.
Additionally a test case is added to confirm that this error works.
This fixes#34458
Note: this is only one out of a few possible ways to fix the issue
depending on how the asm! macro formatting is wanted.
Additionally, it'd be nicer to have some kind of test or feedback
from llvm if the clobber constraints are valid, but I do not know
enough about llvm to say if or how this is possible.
bors
Guillaume Gomez
Michael Woerister
James Miller
Ivan Nejgebauer
petrochenkov
Manish Goregaokar
Mike Hommey
Corey Farwell