"Handle" calls to upstream monomorphizations in compiler_builtins
This is pretty cooked, but I think it works.
compiler-builtins has a long-standing problem that at link time, its rlib cannot contain any calls to `core`. And yet, in codegen we _love_ inserting calls to symbols in `core`, generally from various panic entrypoints.
I intend this PR to attack that problem as completely as possible. When we generate a function call, we now check if we are generating a function call from `compiler_builtins` and whether the callee is a function which was not lowered in the current crate, meaning we will have to link to it.
If those conditions are met, actually generating the call is asking for a linker error. So we don't. If the callee diverges, we lower to an abort with the same behavior as `core::intrinsics::abort`. If the callee does not diverge, we produce an error. This means that compiler-builtins can contain panics, but they'll SIGILL instead of panicking. I made non-diverging calls a compile error because I'm guessing that they'd mostly get into compiler-builtins by someone making a mistake while working on the crate, and compile errors are better than linker errors. We could turn such calls into aborts as well if that's preferred.
fix `long-linker-command-lines` failure caused by `rust.rpath=false`
Fixes `long-linker-command-lines` test failure (which happens when `rust.rpath` is set to `false`) by adjusting `LD_LIBRARY_PATH`.
Fixes https://github.com/rust-lang/rust/issues/90921
This commit rewrites a number of `run-make` tests centered around wasm
to instead use `rmake.rs` and additionally use the `wasm32-wasip1`
target instead of `wasm32-unknown-unknown`. Testing no longer requires
Node.js and additionally uses the `wasmparser` crate from crates.io to
parse outputs and power assertions.
Expose the Freeze trait again (unstably) and forbid implementing it manually
non-emoji version of https://github.com/rust-lang/rust/pull/121501
cc #60715
This trait is useful for generic constants (associated consts of generic traits). See the test (`tests/ui/associated-consts/freeze.rs`) added in this PR for a usage example. The builtin `Freeze` trait is the only way to do it, users cannot work around this issue.
It's also a useful trait for building some very specific abstrations, as shown by the usage by the `zerocopy` crate: https://github.com/google/zerocopy/issues/941
cc ```@RalfJung```
T-lang signed off on reexposing this unstably: https://github.com/rust-lang/rust/pull/121501#issuecomment-1969827742
Fixing shellcheck comments on lvi test script
Running `shellcheck` on `tests/run-make/x86_64-fortanix-unknown-sgx-lvi/script.sh` gives plenty of warnings. This PR fixes those issues. For completeness: #121683 fixes another warning as well
Fix LVI tests after frame pointers are enabled by default
#121203 enables frame pointers by default. This affects LVI mitigations for the `x86_64-fortanix-unknown-sgx` target. LVI remained mitigated correctly, but the tests were too strict.
``@nshyrei`` , ``@jethrogb``
Introduce `run-make` V2 infrastructure, a `run_make_support` library and port over 2 tests as example
## Preface
See [issue #40713: Switch run-make tests from Makefiles to rust](https://github.com/rust-lang/rust/issues/40713) for more context.
## Basic Description of `run-make` V2
`run-make` V2 aims to eliminate the dependency on `make` and `Makefile`s for building `run-make`-style tests. Makefiles are replaced by *recipes* (`rmake.rs`). The current implementation runs `run-make` V2 tests in 3 steps:
1. We build the support library `run_make_support` which the `rmake.rs` recipes depend on as a tool lib.
2. We build the recipe `rmake.rs` and link in the support library.
3. We run the recipe to build and run the tests.
`rmake.rs` is basically a replacement for `Makefile`, and allows running arbitrary Rust code. The support library is built using cargo, and so can depend on external crates if desired.
The infrastructure implemented by this PR is very barebones, and is the minimally required infrastructure needed to build, run and pass the two example `run-make` tests ported over to the new infrastructure.
### Example `run-make` V2 test
```rs
// ignore-tidy-linelength
extern crate run_make_support;
use std::path::PathBuf;
use run_make_support::{aux_build, rustc};
fn main() {
aux_build()
.arg("--emit=metadata")
.arg("stable.rs")
.run();
let mut stable_path = PathBuf::from(env!("TMPDIR"));
stable_path.push("libstable.rmeta");
let output = rustc()
.arg("--emit=metadata")
.arg("--extern")
.arg(&format!("stable={}", &stable_path.to_string_lossy()))
.arg("main.rs")
.run();
let stderr = String::from_utf8_lossy(&output.stderr);
let version = include_str!(concat!(env!("S"), "/src/version"));
let expected_string = format!("stable since {}", version.trim());
assert!(stderr.contains(&expected_string));
}
```
## Follow Up Work
- [ ] Adjust rustc-dev-guide docs
test: enable `unpacked-lto` tests
This enables the correct `unpacked-lto` tests.
Not sure whether `.o` should be removed.
They are bitcode for linker-plugin-lto, though there might be some `.o` for `#[no_builtins]`?
rename 'try' intrinsic to 'catch_unwind'
The intrinsic has nothing to do with `try` blocks, and corresponds to the stable `catch_unwind` function, so this makes a lot more sense IMO.
Also rename Miri's special function while we are at it, to reflect the level of abstraction it works on: it's an unwinding mechanism, on which Rust implements panics.
Allow tests to specify a `//@ filecheck-flags:` header
This allows individual codegen/assembly/mir-opt tests to pass extra flags to the LLVM `filecheck` tool as needed.
---
The original motivation was noticing that `tests/run-make/instrument-coverage` was very close to being an ordinary codegen test, except that it needs some extra logic to set up platform-specific variables to be passed into filecheck.
I then saw the comment in `verify_with_filecheck` indicating that a `filecheck-flags` header might be useful for other purposes as well.
Always use WaitOnAddress on Win10+
`WaitOnAddress` and `WakeByAddressSingle` are always available since Windows 8 so they can now be used without needing to delay load. I've also moved the Windows 7 thread parking fallbacks into a separate sub-module.
This test was already very close to being an ordinary codegen test, except that
it needed some extra logic to set a few variables based on (target) platform
characteristics.
Now that we have support for `//@ filecheck-flags:`, we can instead set those
variables using the normal test revisions mechanism.
llvm: change data layout bug to an error and make it trigger more
Fixes#33446.
Don't skip the inconsistent data layout check for custom LLVMs or non-built-in targets.
With #118708, all targets will have a simple test that would trigger this error if LLVM's data layouts do change - so data layouts would be corrected during the LLVM upgrade. Therefore, with builtin targets, this error won't happen with our LLVM because each target will have been confirmed to work. With non-builtin targets, this error is probably useful to have because you can change the data layout in your target and if it is wrong then that could lead to bugs.
When using a custom LLVM, the same justification makes sense for non-builtin targets as with our LLVM, the user can update their target to match their LLVM and that's probably a good thing to do. However, with a custom LLVM, the user cannot change the builtin target data layouts if they don't match - though given that the compiler's data layout is used for layout computation and a bunch of other things - you could get some bugs because of the mismatch and probably want to know about that. I'm not sure if this is something that people do and is okay, but I doubt it?
`CFG_LLVM_ROOT` was also always set during local development with `download-ci-llvm` so this bug would never trigger locally.
In #33446, two points are raised:
- In the issue itself, changing this from a `bug!` to a proper error is what is suggested, by using `isCompatibleDataLayout` from LLVM, but that function still just does the same thing that we do and check for equality, so I've avoided the additional code necessary to do that FFI call.
- `@Mark-Simulacrum` suggests a different check is necessary to maintain backwards compatibility with old LLVM versions. I don't know how often this comes up, but we can do that with some simple string manipulation + LLVM version checks as happens already for LLVM 17 just above this diff.
Don't skip the inconsistent data layout check for custom LLVMs.
With #118708, all targets will have a simple test that would trigger this
check if LLVM's data layouts do change - so data layouts would be
corrected during the LLVM upgrade. Therefore, with builtin targets, this
check won't trigger with our LLVM because each target will have been
confirmed to work. With non-builtin targets, this check is probably
useful to have because you can change the data layout in your target and
if its wrong then that could lead to bugs.
When using a custom LLVM, the same justification makes sense for
non-builtin targets as with our LLVM, the user can update their target to
match their LLVM and that's probably a good thing to do. However, with
a custom LLVM, the user cannot change the builtin target data layouts if
they don't match - though given that the compiler's data layout is used
for layout computation and a bunch of other things - you could get some
bugs because of the mismatch and probably want to know about that.
`CFG_LLVM_ROOT` was also always set during local development with
`download-ci-llvm` so this bug would never trigger locally.
Signed-off-by: David Wood <david@davidtw.co>
libtest: Fix padding of benchmarks run as tests
### Summary
The first commit adds regression tests for libtest padding.
The second commit fixes padding for benches run as tests and updates the blessed output of the regression tests to make it clear what effect the fix has on padding.
Closes#104092 which is **E-help-wanted** and **regression-from-stable-to-stable**
### More details
Before this fix we applied padding _before_ manually doing what `convert_benchmarks_to_tests()` does which affects padding calculations. Instead use `convert_benchmarks_to_tests()` first if applicable and then apply padding afterwards so it becomes correct.
Benches should only be padded when run as benches to make it easy to compare the benchmark numbers. Not when run as tests.
r? `@ghost` until CI passes.
The output is produced by printf from C code in these cases, and printf prints in text mode, which means `\n` will be printed as `\r\n` on Windows.
In --bless mode the new output with `\r\n` will replace expected output in `tests/run-make/raw-dylib-*\output.txt` files, which use \n, always resulting in dirty files in the repo.
`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.
Before this fix we applied padding before manually doing what
`convert_benchmarks_to_tests()` does. Instead use
`convert_benchmarks_to_tests()` if applicable and then apply padding
afterwards so it becomes correct. (Benches should only be padded when
run as benches to make it easy to compare the benchmark numbers.)
`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`
As you can see the padding is wrong when running benches as tests. This
will be fixed in the next commit. (Benches should only be padded when
run as benches to make it easy to compare the benchmark numbers.)
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`
