Revert "correct subtle bug in the type variable code"
This reverts commit ccd92c2a4e.
This commit is the source of a major perf regression, and was not
intended to be included in #47861. At some point I must have
accidentally re-added the commit.
Fixes#48660.
r? @nikomatsakis
This reverts commit ccd92c2a4e.
This commit is the source of a major perf regression, and was not
intended to be included in #47861. At some point I must have
accidentally re-added the commit.
Currently rustc isn't always the best at producing deterministic builds of a
crate when the source directory of a crate is changed. This is happening due to
what appears two different sources:
* First the `-L` paths passed to rustc are hashed into the crate hash. These
paths through Cargo are typically absolute paths that can vary if the build
directory changes.
* Next the paths passed to `--extern` are also hashed which like `-L` can change
if the build directory changes.
This commit fixes these two sources of nondeterminism by ensuring that avoiding
tracking the hashes of these arguments on the command line. For `-L` paths
they're either related to loading crates (whose hashes are tracked elsewhere) or
native librarise used in the linking phase (which isn't incremental). The
`--extern` paths are similar in that they're related to crate resolution which
is already tracked independently of the command line arguments.
Closes#48019
Support parentheses in patterns under feature gate
This is a prerequisite for any other extensions to pattern syntax - `|` with multiple patterns, type ascription, `..PAT` in slice patterns.
Closes https://github.com/rust-lang/rfcs/issues/554
These changes were meant to be in
2b18d8fe9dc05415a8e6b7cadf879c7f7ebe020a (rebased from
12a230562e), but I messed up the rebase a
bit as the file had been moved.
This should not be needed: the new variable will be related to the old
ones, so if they are constrained, so is the new variable; if they are
not, and hence default to diverging, so will the new variable.
Introduce UnpackedKind
This adds an `UnpackedKind` type as a typesafe counterpart to `Kind`. This should make future changes to kinds (such as const generics!) more resilient, as the type-checker will be able to catch more potential issues.
r? @eddyb
cc @yodaldevoid
