`tokenstream::Spacing` appears on all `TokenTree::Token` instances,
both punct and non-punct. Its current usage:
- `Joint` means "can join with the next token *and* that token is a
punct".
- `Alone` means "cannot join with the next token *or* can join with the
next token but that token is not a punct".
The fact that `Alone` is used for two different cases is awkward.
This commit augments `tokenstream::Spacing` with a new variant
`JointHidden`, resulting in:
- `Joint` means "can join with the next token *and* that token is a
punct".
- `JointHidden` means "can join with the next token *and* that token is a
not a punct".
- `Alone` means "cannot join with the next token".
This *drastically* improves the output of `print_tts`. For example,
this:
```
stringify!(let a: Vec<u32> = vec![];)
```
currently produces this string:
```
let a : Vec < u32 > = vec! [] ;
```
With this PR, it now produces this string:
```
let a: Vec<u32> = vec![] ;
```
(The space after the `]` is because `TokenTree::Delimited` currently
doesn't have spacing information. The subsequent commit fixes this.)
The new `print_tts` doesn't replicate original code perfectly. E.g.
multiple space characters will be condensed into a single space
character. But it's much improved.
`print_tts` still produces the old, uglier output for code produced by
proc macros. Because we have to translate the generated code from
`proc_macro::Spacing` to the more expressive `token::Spacing`, which
results in too much `proc_macro::Along` usage and no
`proc_macro::JointHidden` usage. So `space_between` still exists and
is used by `print_tts` in conjunction with the `Spacing` field.
This change will also help with the removal of `Token::Interpolated`.
Currently interpolated tokens are pretty-printed nicely via AST pretty
printing. `Token::Interpolated` removal will mean they get printed with
`print_tts`. Without this change, that would result in much uglier
output for code produced by decl macro expansions. With this change, AST
pretty printing and `print_tts` produce similar results.
The commit also tweaks the comments on `proc_macro::Spacing`. In
particular, it refers to "compound tokens" rather than "multi-char
operators" because lifetimes aren't operators.
Avoid adding builtin functions to `symbols.o`
We found performance regressions in #113923. The problem seems to be that `--gc-sections` does not remove these symbols. I tested that lld removes these symbols, but ld and gold do not.
I found that `used` adds symbols to `symbols.o` at 3e202ead60/compiler/rustc_codegen_ssa/src/back/linker.rs (L1786-L1791).
The PR removes builtin functions.
Note that under LTO, ld still preserves these symbols. (lld will still remove them.)
The first commit also fixes#118559. But I think the second commit also makes sense.
`build_session` is passed an `EarlyErrorHandler` and then constructs a
`Handler`. But the `EarlyErrorHandler` is still used for some time after
that.
This commit changes `build_session` so it consumes the passed
`EarlyErrorHandler`, and also drops it as soon as the `Handler` is
built. As a result, `parse_cfg` and `parse_check_cfg` now take a
`Handler` instead of an `EarlyErrorHandler`.
Report errors in jobserver inherited through environment variables
This pr attempts to catch situations, when jobserver exists, but is not being inherited.
r? `@petrochenkov`
Restore `#![no_builtins]` crates participation in LTO.
After #113716, we can make `#![no_builtins]` crates participate in LTO again.
`#![no_builtins]` with LTO does not result in undefined references to the error. I believe this type of issue won't happen again.
Fixes#72140. Fixes#112245. Fixes#110606. Fixes#105734. Fixes#96486. Fixes#108853. Fixes#108893. Fixes#78744. Fixes#91158. Fixes https://github.com/rust-lang/cargo/issues/10118. Fixes https://github.com/rust-lang/compiler-builtins/issues/347.
The `nightly-2023-07-20` version does not always reproduce problems due to changes in compiler-builtins, core, and user code. That's why this issue recurs and disappears.
Some issues were not tested due to the difficulty of reproducing them.
r? pnkfelix
cc `@bjorn3` `@japaric` `@alexcrichton` `@Amanieu`
Added linker_arg(s) Linker trait methods for link-arg to be prefixed "-Wl," for cc-like linker args and not verbatim
https://github.com/rust-lang/rust/issues/99427#issuecomment-1234443468
> here's one possible improvement to -l link-arg making it more portable between linkers and useful - befriending it with the verbatim modifier (https://github.com/rust-lang/rust/issues/99425).
>
> -l link-arg:-verbatim=-foo would add -Wl,-foo (or equivalent) when C compiler is used as a linker, and just -foo when bare linker is used.
> -l link-arg:+verbatim=-bar on the other hand would always pass just -bar.
They've been deprecated for four years.
This commit includes the following changes.
- It eliminates the `rustc_plugin_impl` crate.
- It changes the language used for lints in
`compiler/rustc_driver_impl/src/lib.rs` and
`compiler/rustc_lint/src/context.rs`. External lints are now called
"loaded" lints, rather than "plugins" to avoid confusion with the old
plugins. This only has a tiny effect on the output of `-W help`.
- E0457 and E0498 are no longer used.
- E0463 is narrowed, now only relating to unfound crates, not plugins.
- The `plugin` feature was moved from "active" to "removed".
- It removes the entire plugins chapter from the unstable book.
- It removes quite a few tests, mostly all of those in
`tests/ui-fulldeps/plugin/`.
Closes#29597.
Allow target specs to use an LLD flavor, and self-contained linking components
This PR allows:
- target specs to use an LLD linker-flavor: this is needed to switch `x86_64-unknown-linux-gnu` to using LLD, and is currently not possible because the current flavor json serialization fails to roundtrip on the modern linker-flavors. This can e.g. be seen in https://github.com/rust-lang/rust/pull/115622#discussion_r1321312880 which explains where an `Lld::Yes` is ultimately deserialized into an `Lld::No`.
- target specs to declare self-contained linking components: this is needed to switch `x86_64-unknown-linux-gnu` to using `rust-lld`
- adds an end-to-end test of a custom target json simulating `x86_64-unknown-linux-gnu` being switched to using `rust-lld`
- disables codegen backends from participating because they don't support `-Zgcc-ld=lld` which is the basis of mcp510.
r? `@petrochenkov:` if the approach discussed https://github.com/rust-lang/rust/pull/115622#discussion_r1329403467 and on zulip would work for you: basically, see if we can emit only modern linker flavors in the json specs, but accept both old and new flavors while reading them, to fix the roundtrip issue.
The backwards compatible `LinkSelfContainedDefault` variants are still serialized and deserialized in `crt-objects-fallback`, while the spec equivalent of e.g. `-Clink-self-contained=+linker` is serialized into a different json object (with future-proofing to incorporate `crt-objects-fallback` in the future).
---
I've been test-driving this in https://github.com/rust-lang/rust/pull/113382 to test actually switching `x86_64-unknown-linux-gnu` to `rust-lld` (and fix what needs to be fixed in CI, bootstrap, etc), and it seems to work fine.
Chrome links .rlibs with /WHOLEARCHIVE or -Wl,--whole-archive to prevent
the linker from discarding static initializers. This works well, except
on Windows x86, where lld complains:
error: /safeseh: lib.rmeta is not compatible with SEH
The fix is simply to mark the .rmeta as SAFESEH aware. This is trivially
true, since the metadata file does not contain any executable code.
Most coverage metadata is encoded into two sections in the final executable.
The `__llvm_covmap` section mostly just contains a list of filenames, while the
`__llvm_covfun` section contains encoded coverage maps for each instrumented
function.
The catch is that each per-function record also needs to contain a hash of the
filenames list that it refers to. Historically this was handled by assembling
most of the per-function data into a temporary list, then assembling the
filenames buffer, then using the filenames hash to emit the per-function data,
and then finally emitting the filenames table itself.
However, now that we build the filenames table up-front (via a separate
traversal of the per-function data), we can hash and emit that part first, and
then emit each of the per-function records immediately after building. This
removes the awkwardness of having to temporarily store nearly-complete
per-function records.
Mention the syntax for `use` on `mod foo;` if `foo` doesn't exist
Newcomers might get confused that `mod` is the only way of defining scopes, and that it can be used as if it were `use`.
Fix#69492.
Implement rustc part of RFC 3127 trim-paths
This PR implements (or at least tries to) [RFC 3127 trim-paths](https://github.com/rust-lang/rust/issues/111540), the rustc part. That is `-Zremap-path-scope` with all of it's components/scopes.
`@rustbot` label: +F-trim-paths
Use `YYYY-MM-DDTHH_MM_SS` as datetime format for ICE dump files
Windows paths do not support `:`, so use a datetime format in ICE dump paths that Windows will accept.
CC #116809, fix#115180.
MacOS (and all apple targets) have -Csplit-debuginfo=packed as default
instead of "off" like all other targets (well there is Windows, but we
don't test it in those tests), also -Csplit-debuginfo is not stable on
all targets so we only set in on Darwin where is matters.
When building with LTO, builtin functions that are defined but whose calls have not been inserted yet, get internalized.
We need to prevent these symbols from being internalized at LTO time.
Refer to https://reviews.llvm.org/D49434.
After #113716, we can make `#![no_builtins]` crates participate in LTO again.
`#![no_builtins]` with LTO does not result in undefined references to the error.
The `rustc_span::FileName` enum already differentiates between real
files and "fake" files such as `<anon>`. We do not need to artificially
forbid real file names from ending in `>`.
stabilize combining +bundle and +whole-archive link modifiers
Per discussion on https://github.com/rust-lang/rust/issues/108081 combining +bundle and +whole-archive already works and can be stabilized independently of other aspects of the packed_bundled_libs feature. There is no risk of regression because this was not previously allowed.
r? `@petrochenkov`
Raise minimum supported Apple OS versions
This implements the proposal to raise the minimum supported Apple OS versions as laid out in the now-completed MCP (https://github.com/rust-lang/compiler-team/issues/556).
As of this PR, rustc and the stdlib now support these versions as the baseline:
- macOS: 10.12 Sierra
- iOS: 10
- tvOS: 10
- watchOS: 5 (Unchanged)
In addition to everything this breaks indirectly, these changes also erase the `armv7-apple-ios` target (currently tier 3) because the oldest supported iOS device now uses ARMv7s. Not sure what the policy around tier3 target removal is but shimming it is not an option due to the linker refusing.
[Per comment](https://github.com/rust-lang/compiler-team/issues/556#issuecomment-1297175073), this requires a FCP to merge. cc `@wesleywiser.`
[breaking change] Validate crate name in `--extern` [MCP 650]
Reject non-ASCII-identifier crate names passed to the CLI option `--extern` (`rustc`, `rustdoc`).
Implements [MCP 650](https://github.com/rust-lang/compiler-team/issues/650) (except that we only allow ASCII identifiers not arbitrary Rust identifiers).
Fixes#113035.
[As mentioned on Zulip](https://rust-lang.zulipchat.com/#narrow/stream/233931-t-compiler.2Fmajor-changes/topic/Disallow.20non-identifier-valid.20--extern.20cr.E2.80.A6.20compiler-team.23650/near/376826988), doing a crater run probably doesn't make sense since it wouldn't yield anything. Most users don't interact with `rustc` directly but only ever through Cargo which always passes a valid crate name to `--extern` when it invokes `rustc` and `rustdoc`. In any case, the user wouldn't be able to use such a crate name in the source code anyway.
Note that I'm not using [`rustc_session::output::validate_crate_name`](https://doc.rust-lang.org/nightly/nightly-rustc/rustc_session/output/fn.validate_crate_name.html) (used for `--crate-name` and `#![crate_name]`) since the latter doesn't reject non-ASCII crate names and ones that start with a digit.
As an aside, I've also thought about getting rid of `validate_crate_name` entirely in a separate PR (with another MCP) in favor of `is_ascii_ident` to reject more weird `--crate-name`s, `#![crate_name]`s and file names but I think that would lead to a lot of actual breakage, namely because of file names starting with a digit. In `tests/ui` 9 tests would be impacted for example.
CC `@estebank`
r? `@est31`
