According to Apple's [arm64 calling convention](https://developer.apple.com/library/ios/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARM64FunctionCallingConventions.html#//apple_ref/doc/uid/TP40013702-SW1) varargs always are passed
through stack. Since `open` is actually a vararg function on Darwin,
it means that older declaration caused permissions to be taken from
stack, while passed through register => it set file permissions
to garbage and it was simply impossible to read/delete files after they
were created.
They way this commit handles it is to preserve compatibility with
existing code - it simply creates a shim unsafe function so all existing
callers continue work as nothing happened.
The main gist of this PR is commit 1077efb which removes the list of supertraits from the `TraitDef` and pulls them into a separate table, which is accessed via `lookup_super_predicates`. This is analogous to `lookup_predicates`, which gets the complete where clause. This allows us to create the `TraitDef`, which contains the list generics and so forth, without fully knowing the list of supertraits. This in turn allows the *supertrait listing* to contain references to associated types like `<Self as Foo>::Item`, which were previously impossible because conversion required having the `TraitDef` for `Foo`.
We do not yet support `Self::Item` in a supertrait listing. This doesn't work because to convert that, it attempts to expand out the full set of supertraits, which are in the process of being created. This could potentially be worked out by having the expansion of supertraits proceed in a lazy fashion, but we'd have to define shadowing rules for associated types which we don't currently have.
Along the way (in 9de9ec5) I also removed the restriction against duplicate bounds and generalized the code so that it can handle having the same supertrait multiple times with different arguments, e.g. `Foo : Bar<i32> + Bar<u32>`. This restriction was serving no particular purpose, since the same trait could be extended multiple times indirectly, and in the era of multidispatch it is actively harmful.
This is technically a [breaking-change] because it affects the definition of a super-trait. Anything in a where clause that looks like `where Self : Foo` is now considered a supertrait. Because cycles are disallowed in supertraits, that could lead to some errors. This has not been observed in any existing code.
r? @nrc
According to Apple arm64 calling convention varargs always are passed
through stack. Since `open` is actually a vararg function on Darwin's,
it means that older declaration caused permissions to be taken from
stack, while passed through register => it set file permissions
to garbage and it was simply impossible to read/delete files after they
were created.
They way this commit handles it is to preserve compatibility with
existing code - it simply creates a shim unsafe function so all existing
callers continue work as nothing happened.
Automatic has-same-types testing methodology can be found in #22501.
Because most of them don't work with `--pretty=typed`, compile-fail tests were manually audited.
r? @aturon
Automatic has-same-types testing methodology can be found in #22501.
Because most of them don't work with `--pretty=typed`, compile-fail tests were manually audited.
r? @aturon
This same source is being built in the Cargo ecosystem and hence needs to build
on stable Rust as well. This commit places the `no_std` attribute along with the
`no_std` feature behind a `cfg_attr` flag so they are not processed when
compiled on crates.io
This stability attribute was left out by accident and the stability pass has
since picked up the ability to check for this. As a result, crates are currently
getting warnings for implementations of `Index`.
Updates to the bison grammar to account for recent grammar additions and new tests. In particular:
* Support parsing `impl MyTrait for .. { }`
* Support parsing ExprQualifiedPaths without \"as TRAIT_REF\" such as `<Foo>::bar(&Foo)`
* Support parsing \"for\" clauses at the beginning of where clauses such as `where for<'a, 'b> &'a T: Bar<'b>`
Currently, the list of files linted in `tidy.py` is unordered. It seems more appropriate for more frequently appearing files (like `.rs`) to appear at the top of the list and for \"other files\" to appear at the very end. This PR also changes the wildcard import of `check_license()` into an explicit one.
```
Before: After:
* linted 4 .sh files * linted 5034 .rs files
* linted 4 .h files * linted 29 .c files
* linted 29 .c files * linted 28 .py files
* linted 2 .js files * linted 4 .sh files
* linted 0 other files * linted 4 .h files
* linted 28 .py files * linted 2 .js files
* linted 5034 .rs files * linted 0 other files
```
r? @brson
This commit deprecates the majority of std::old_io::fs in favor of std::fs and
its new functionality. Some functions remain non-deprecated but are now behind a
feature gate called `old_fs`. These functions will be deprecated once
suitable replacements have been implemented.
The compiler has been migrated to new `std::fs` and `std::path` APIs where
appropriate as part of this change.
[breaking-change]
This commit deprecates the majority of std::old_io::fs in favor of std::fs and
its new functionality. Some functions remain non-deprecated but are now behind a
feature gate called `old_fs`. These functions will be deprecated once
suitable replacements have been implemented.
The compiler has been migrated to new `std::fs` and `std::path` APIs where
appropriate as part of this change.
us to construct trait-references and do other things without forcing a
full evaluation of the supertraits. One downside of this scheme is that
we must invoke `ensure_super_predicates` before using any construct that
might require knowing about the super-predicates.
This allows to create proper debuginfo line information for items inlined from other crates (e.g. instantiations of generics). Only the codemap's 'metadata' is stored in a crate's metadata. That is, just filename, positions of line-beginnings, etc. but not the actual source code itself.
Crate metadata size is increased by this change because spans in the encoded ASTs take up space now:
```
BEFORE AFTER
libcore 36 MiB 39.6 MiB +10%
libsyntax 51.1 MiB 60.5 MiB +18.4%
libcollections 11.2 MiB 12.8 MiB +14.3%
```
This only affects binaries containing metadata (rlibs and dylibs), executables should not be affected in size.
Fixes#19228 and probably #22226.
