Move has_panic_handler to query
Moves us off of a global Once instead re-querying the lang item each time. The conditions on when we set it to true change a little (previously we'd make sure a few more lang items were `Some`) but I think they in practice don't matter, we won't compile later on if we don't have them.
Don't hide ICEs from previous incremental compiles
I think this fixes#65401, the compiler does not fail to ICE after the first compilation, tested on the last snippet of [this comment](https://github.com/rust-lang/rust/issues/63154#issuecomment-541592381).
I am not very sure of the fix as I don't understand much of the structure of the compiler.
The value names are used when reporting issues found by address
sanitizer or memory sanitizer. Avoid discarding names when those
sanitizers are enabled, unless explicitly requested to do otherwise.
SelfProfiler API refactoring and part one of event review
This PR refactors the `SelfProfiler` a little bit so that most profiling methods are RAII-based. The codegen backend code already had something similar, this refactoring pulls this functionality up into `SelfProfiler` itself, for general use.
The second commit of this PR is a review and update of the existing events we are already recording. Names have been made more consistent. CGU names have been removed from event names. They will be added back in when function parameter recording is implemented.
There is still some work to be done for adding new events, especially around trait resolution and the incremental system.
r? @wesleywiser
Make all alt builders produce parallel-enabled compilers
We're not quite ready to ship parallel compilers by default, but the alt
builders are not used too much (in theory), so we believe that shipping
a possibly-broken compiler there is not too problematic.
r? @nikomatsakis
This changes the default parallelism for parallel compilers to one,
instead of the previous default, which was "num cpus". This is likely
not an optimal default long-term, but it is a good default for testing
whether parallel compilers are not a significant regression over a
sequential compiler.
Notably, this in theory makes a parallel-enabled compiler behave
exactly like a sequential compiler with respect to the jobserver.
rustc: Fix mixing crates with different `share_generics`
This commit addresses #64319 by removing the `dylib` crate type from the
list of crate type that exports generic symbols. The bug in #64319
arises because a `dylib` crate type was trying to export a symbol in an
uptream crate but it miscalculated the symbol name of the uptream
symbol. This isn't really necessary, though, since `dylib` crates aren't
that heavily used, so we can just conservatively say that the `dylib`
crate type never exports generic symbols, forcibly removing them from
the exported symbol lists if were to otherwise find them.
The fix here happens in two places:
* First is in the `local_crate_exports_generics` method, indicating that
it's now `false` for the `Dylib` crate type. Only rlibs actually
export generics at this point.
* Next is when we load exported symbols from upstream crate. If, for our
compilation session, the crate may be included from a dynamic library,
then its generic symbols are removed. When the crate was linked into a
dynamic library its symbols weren't exported, so we can't consider
them a candidate to link against.
Overally this should avoid situations where we incorrectly calculate the
upstream symbol names in the face of differnet `share_generics` options,
ultimately...
Closes#64319
This commit converts a field of `Session`, `dependency_formats`, into a
query of `TyCtxt`. This information then also needed to be threaded
through to other remaining portions of the linker, but it's relatively
straightforward. The only change here is that instead of
`HashMap<CrateType, T>` the data structure changed to `Vec<(CrateType,
T)>` to make it easier to deal with in queries.
When `rustc` is invoked with the `--print` argument, we don't actually
generate any code (unless it's the `native-static-libs` option). So we
don't need to error our in this case since there's no risk of generating
either LLVM assertions or corrupted binaries.
Stabilize support for Profile-guided Optimization
This PR makes profile-guided optimization available via the `-C profile-generate` / `-C profile-use` pair of commandline flags and adds end-user documentation for the feature to the [rustc book](https://doc.rust-lang.org/rustc/). The PR thus ticks the last two remaining checkboxes of the [stabilization tracking issue](https://github.com/rust-lang/rust/issues/59913).
From the tracking issue:
> Profile-guided optimization (PGO) is a common optimization technique for ahead-of-time compilers. It works by collecting data about a program's typical execution (e.g. probability of branches taken, typical runtime values of variables, etc) and then uses this information during program optimization for things like inlining decisions, machine code layout, or indirect call promotion.
If you are curious about how this can be used, there is a rendered version of the documentation this PR adds available [here](
https://github.com/michaelwoerister/rust/blob/stabilize-pgo/src/doc/rustc/src/profile-guided-optimization.md).
r? @alexcrichton
cc @rust-lang/compiler
The proper name of the library is `annotate-snippet`, not `annotate-rs`,
this commit should get rid of any confusing `AnnotateRs` names.
1. Renames `annotate_rs_emitter.rs` to
`annotate_snippet_emitter_writer.rs` so that the difference between the
`Emitter` trait and the implementers is more clear.
2. Renames `AnnotateRsEmitterWriter` to `AnnotateSnippetEmitterWriter`
3. Renames `HumanReadableErrorType::AnnotateRs` to `HumanReadableErrorType::AnnotateSnippet`
Emit error when trying to use PGO in conjunction with unwinding on Windows.
This PR makes `rustc` emit an error when trying use PGO in conjunction with `-Cpanic=unwind` on Windows, isn't supported by LLVM yet. The error messages points to https://github.com/rust-lang/rust/issues/61002, which documents this known limitation.
Suggest appropriate path when calling associated item on bare types
When looking at the documentation for `std::f32` or `std::str`, for
example, it is easy to get confused and assume `std::f32` and `f32`
are the same thing. Because of this, it is not uncommon to attempt
writing `f32::consts::PI` instead of the correct
`std::f32::consts::PI`. When encountering the former, which results
in an access error due to it being an inexistent path, try to access
the same path under `std`. If this succeeds, this information is
stored for later tweaking of the final E0599 to provide an
appropriate suggestion.
Fix#26760, fix#46660.
When looking at the documentation for `std::f32` or `std::str`, for
example, it is easy to get confused and assume `std::f32` and `f32`
are the same thing. Because of this, it is not uncommon to attempt
writing `f32::consts::PI` instead of the correct
`std::f32::consts::PI`. When encountering the former, which results
in an access error due to it being an inexistent path, try to access
the same path under `std`. If this succeeds, this information is
stored for later tweaking of the final E0599 to provide an
appropriate suggestion.
This suggestion applies to both E0233 and E0599 and is only checked
when the first ident of a path corresponds to a primitive type.
