Add disclaimer on size assertion macro
Sometimes people are inspired by rustc to add size assertions to their code and copy the macro. This is bad because it causes hard build errors. rustc happens to be special where it makes this okay.
For example, see #115028 (not sure whether they were directly inspired by this function), but I think I've also seen other cases.
Warn on elided lifetimes in associated constants (`ELIDED_LIFETIMES_IN_ASSOCIATED_CONSTANT`)
Elided lifetimes in associated constants (in impls) erroneously resolve to fresh lifetime parameters on the impl since #97313. This is not correct behavior (see #38831).
I originally opened #114716 to fix this, but given the time that has passed, the crater results seem pretty bad: https://github.com/rust-lang/rust/pull/114716#issuecomment-1682091952
This PR alternatively implements a lint against this behavior, and I'm hoping to bump this to deny in a few versions.
Redefine the pluralize macro's arm
Redefine the unintuitive pluralize macro's arm because of the negation. The initial code starts with check if count is not 1, which is confusing and unintuitive.
The arm shoud start with checking,
- if "count" `is 1` then, append `""` (empty string) - indicate as singular
- Then check if "count" `is not 1` (more than 1), append `"s"` - indicate as plural
Before:
```rs
// This arm is abit confusing since it start with checking, if "count" is more than 1, append "s".
($x:expr) => {
if $x != 1 { "s" } else { "" }
};
```
After:
```rs
// Pluralize based on count (e.g., apples)
($x:expr) => {
if $x == 1 { "" } else { "s" }
};
```
Coverage statements in MIR are heavily tied to internal details of the coverage
implementation that are likely to change, and are unlikely to be useful to
third-party tools for the foreseeable future.
Sometimes people are inspired by rustc to add size assertions to their
code and copy the macro. This is bad because it causes hard build
errors. rustc happens to be special where it makes this okay.
As of Xcode 15 Apple's linker has become a bit more strict about the
warnings it produces. One of those new warnings requires all valid
Mach-O object files in an archive to have a LC_BUILD_VERSION load
command:
```
ld: warning: no platform load command found in 'ARCHIVE[arm64][2106](lib.rmeta)', assuming: iOS-simulator
```
This was already being done for Mac Catalyst so this change expands this
logic to include it for all Apple platforms. I filed this behavior
change as FB12546320 and was told it was the new intentional behavior.
coverage: Give the instrumentor its own counter type, separate from MIR
Within the MIR representation of coverage data, `CoverageKind` is an important part of `StatementKind::Coverage`, but the `InstrumentCoverage` pass also uses it heavily as an internal data structure. This means that any change to `CoverageKind` also needs to update all of the internal parts of `InstrumentCoverage` that manipulate it directly, making the MIR representation difficult to modify.
---
This change fixes that by giving the instrumentor its own `BcbCounter` type for internal use, which is then converted to a `CoverageKind` when injecting coverage information into MIR.
The main change is mostly mechanical, because the initial `BcbCounter` is drop-in compatible with `CoverageKind`, minus the unnecessary `CoverageKind::Unreachable` variant.
I've then removed the `function_source_hash` field from `BcbCounter::Counter`, as a small example of how the two types can now usefully differ from each other. Every counter in a MIR-level function should have the same source hash, so we can supply the hash during the conversion to `CoverageKind::Counter` instead.
---
*Background:* BCB stands for “basic coverage block”, which is a node in the simplified control-flow graph used by coverage instrumentation. The instrumentor pass uses the function's actual MIR control-flow graph to build a simplified BCB graph, then assigns coverage counters and counter expressions to various nodes/edges in that simplified graph, and then finally injects corresponding coverage information into the underlying MIR.
Fix a stack overflow with long else if chains
This fixes stack overflows when running the `issue-74564-if-expr-stack-overflow.rs` test with the parallel compiler.
Add MIR validation for unwind out from nounwind functions + fixes to make validation pass
`@Nilstrieb` This is the MIR validation you asked in https://github.com/rust-lang/rust/pull/112403#discussion_r1222739722.
Two passes need to be fixed to get the validation to pass:
* `RemoveNoopLandingPads` currently unconditionally introduce a resume block (even there is none to begin with!), changed to not do that
* Generator state transform introduces a `assert` which may unwind, and its drop elaboration also introduces many new `UnwindAction`s, so in this case run the AbortUnwindingCalls after the transformation.
I believe this PR should also fixRust-for-Linux/linux#1016, cc `@ojeda`
r? `@Nilstrieb`
custom_mir: change Call() terminator syntax to something more readable
I find our current syntax very hard to read -- I cannot even remember the order of arguments, and having the "next block" *before* the actual function call is very counter-intuitive IMO. So I suggest we use `Call(ret_val = function(v), next_block)` instead.
r? `@JakobDegen`
Ignore unexpected incr-comp session dirs
Clearly the code path can be hit without the presence of a compiler bug.
All it takes is mischief. See #71698.
Ignore problematic directories instead of ICE:ing. `continue`ing is
already done for problematic dirs in the code block above us.
Closes#71698.
With this fix, the output is this instead of ICE:
```
$ cargo +stage1 new gz-ice && cd gz-ice
$ cargo +stage1 build
$ find target -type f -exec gzip {} \;
$ cargo +stage1 run
Created binary (application) `gz-ice` package
Compiling gz-ice v0.1.0 (/tmp/gz-ice)
Finished dev [unoptimized + debuginfo] target(s) in 0.13s
gzip: target/debug/gz-ice has 1 other link -- unchanged
gzip: target/debug/deps/gz_ice-de919414dd9926b9 has 1 other link -- unchanged
Compiling gz-ice v0.1.0 (/tmp/gz-ice)
warning: failed to garbage collect invalid incremental compilation session directory `/tmp/gz-ice/target/debug/incremental/gz_ice-23qx9z9j9vghe/s-gnwd8daity-kp10sj.lock.gz`: Not a directory (os error 20)
warning: `gz-ice` (bin "gz-ice") generated 1 warning
Finished dev [unoptimized + debuginfo] target(s) in 0.13s
Running `target/debug/gz-ice`
Hello, world!
```
Avoid side-effects from `try_coerce` when suggesting borrowing LHS of cast
The name `try_coerce` is a bit misleading -- it has side-effects, so when it's used in diagnostics code, it sometimes causes spurious obligations to be registered which cause other errors to occur that really make no sense in context.
Addendum: let's just rename `try_coerce` to `coerce` -- the `try_` part doesn't really add much, imo.
Normalize return type of `deduce_future_output_from_obligations`
Fixes#114909
Also confirmed to fix#114727 manually
Now that we have weak/lazy type aliases, we need to normalize those in future signatures to ensure that `replace_opaque_types_with_inference_vars` actually sees TAITs behind them. This isn't needed in the new solver, but added a test to make sure it doesn't regress there either.
r? types cc `@oli-obk` (who's gone, worst case can delay this PR until he's back)
Fix ABI flags in RISC-V/LoongArch ELF file generated by rustc
Fix#114153
It turns out the current way to set these flags are completely wrong. In LLVM the target ABI is used instead of target features to determine these flags.
Not sure how to write a test though. Or maybe a test isn't necessary because this affects only those touching target json?
r? `@Nilstrieb`
This shows one small benefit of separating `BcbCounter` from `CoverageKind`.
The function source hash will be the same for all counters within a function,
so instead of passing it through `CoverageCounters` and storing it in every
counter, we can just supply it during the final conversion to `CoverageKind`.
