fix couple of perf related clippy warnings
librustc: don't clone a type that is copy
librustc_incremental: use faster vector initialization
librustc_typeck: don't clone a type that is copy
librustdoc: don't create a vector where a slice will do
Fix 59191 - ICE when macro replaces crate root with non-module item
Hi,
This should fix#59191! My friend and I are working on learning the rustc codebase through contributions, so please feel free to mention anything amiss or that could be done better.
The code adds an explicit case for when a macro applied to the crate root (via an inner attribute) replaces it with something nonsensical, like a function. The crate root must be a module, and the error message reflects this.
---
I should note that there are a few other weird edge cases here, like if they do output a module, it succeeds but uses that module's name as a prefix for all names in the crate. I'm assuming that's an issue for stabilizing #54726, though.
Instrument C / C++ in MemorySanitizer example
Modify the example to instrument C / C++ in addition to Rust, since it
will be generally required (e.g., when using libbacktrace for symbolication).
Tweak obligation error output
- Point at arguments or output when fn obligations come from them, or ident when they don't
- Point at `Sized` bound (fix#47990)
- When object unsafe trait uses itself in associated item suggest using `Self` (fix#66424, fix#33375, partially address #38376, cc #61525)
- Point at reason in object unsafe trait with `Self` in supertraits or `where`-clause (cc #40533, cc #68377)
- On implicit type parameter `Sized` obligations, suggest `?Sized` (fix#57744, fix#46683)
Step stage0 to bootstrap from 1.42
This also includes a commit which fixes the rustfmt downloading logic to redownload when the rustfmt channel changes, and bumps rustfmt to a more recent version.
Always use lazy qualif getters during const-checking
`has_mut_interior_eager_seek` was needed to work around an overly restrictive bound on the `per_local` argument to the `Qualif` trait. This PR makes that bound `FnMut` instead of `Fn` so we can seek cursors inside of it, resolving a FIXME in the const-checking code.
librustc: don't clone a type that is copy
librustc_incremental: use faster vector initialization
librustc_typeck: don't clone a type that is copy
librustdoc: don't create a vector where a slice will do
Implement MIR lowering for or-patterns
This is the last thing needed to get meaningful run-pass tests for or-patterns. There probably need to be more tests before stabilizing this, but the most important cases should have been covered.
Note: we can generate exponentially large MIR CFGs when using or-patterns containing bindings, type ascriptions, or that are for a match arm with a guard. `src/test/mir-opt/exponential-or.rs` shows the best case for what we currently do.
cc #54883closes#60350closes#67514
cc @Centril
r? @pnkfelix
Added upper bound of what vecs and boxes can allocate
Fixed issue #68593
I added a line of documentation to these two files to reflect that vectors and boxes ensure that they never allocate more than `isize::MAX` bytes.
r? @steveklabnik
Install robots.txt into rust-docs tarballs
Fixes#68677.
I believe this might just work out from the central-station perspective, but even if it doesn't, this is a prerequisite step anyway.
codegen: create DIVariables ahead of using them with llvm.dbg.declare.
Instead of having `rustc_codegen_llvm` bundle creation of a `DIVariable` and `llvm.dbg.declare` into a single operation, they are now two separate methods, and the `DIVariable` is created earlier, specifically when `mir::VarDebugInfo`s are being partitioned into locals.
While this isn't currently needed, it's a prerequisite for #48300, which adds fragmented debuginfo, where one `mir::VarDebugInfo` has multiple parts of itself mapped to different `mir::Place`s.
For debuggers to see one composite variable instead of several ones with the same name, we need to create a single `DIVariable` and share it between multiple `llvm.dbg.declare` calls, which are likely pointing to different MIR locals.
That makes the `per_local_var_debug_info` partitioning a good spot to do this in, as we can create *exactly* one `DIVariable` per `mir::VarDebugInfo`, and refer to it as many things as needed.
I'm opening this PR separately because I want to test its perf impact in isolation (see https://github.com/rust-lang/rust/pull/48300#issuecomment-580121438).
r? @nagisa or @oli-obk cc @michaelwoerister @nikomatsakis
Avoid exponential behaviour when relating types
When equating bound types we check subtyping in both directions. Since closures are invariant in their substs, we end up comparing the two types an exponential number of times. If there are no bound variables this isn't needed.
Closes#68061
Changes the error handler for inner attributes that replace the root
with a non-module. Previously it would emit a fatal error. It now emits
an empty expasion and a non-fatal error like the existing handler for a
failed expansion.
