Do not emit type errors on recovered blocks
When a parse error occurs on a block, the parser will recover and create
a block with the statements collected until that point. Now a flag
stating that a recovery has been performed in this block is propagated
so that the type checker knows that the type of the block (which will be
identified as `()`) shouldn't be checked against the expectation to
reduce the amount of irrelevant diagnostic errors shown to the user.
Fix#44579.
When a parse error occurs on a block, the parser will recover and create
a block with the statements collected until that point. Now a flag
stating that a recovery has been performed in this block is propagated
so that the type checker knows that the type of the block (which will be
identified as `()`) shouldn't be checked against the expectation to
reduce the amount of irrelevant diagnostic errors shown to the user.
Prevent rustc overwriting input files
If rustc is invoked on a file that would be overwritten by the
compilation, the compilation now fails, to avoid accidental loss. This
resolves#13019. Kudos to @estebank, whose patch I finished off.
Loading the dependency graph in the background
Patch is a bit longer than I expected, due to the fact that most of this code relies upon a `Session` value, which is not `Sync`.
Help Cargo tolerate RUSTFLAGS="--print=native-static-libs"
Alternative to https://github.com/rust-lang/cargo/pull/4807
Having this "error" message was a mistake, as it's firing at exactly wrong time when Cargo is trying to read the output of other print commands.
[MIR-borrowck] Two phase borrows
This adds limited support for two-phase borrows as described in
http://smallcultfollowing.com/babysteps/blog/2017/03/01/nested-method-calls-via-two-phase-borrowing/
The support is off by default; you opt into it via the flag `-Z two-phase-borrows`
I have written "*limited* support" above because there are simple variants of the simple `v.push(v.len())` example that one would think should work but currently do not, such as the one documented in the test compile-fail/borrowck/two-phase-reservation-sharing-interference-2.rs
(To be clear, that test is not describing something that is unsound. It is just providing an explicit example of a limitation in the implementation given in this PR. I have ideas on how to fix, but I want to land the work that is in this PR first, so that I can stop repeatedly rebasing this branch.)
Having the HIR local id is useful for cases like understanding the
ReScope identifiers, which are now derived from the HIR local id, and
thus one can map an ReScope back to the HIR node, once one knows what
those local ids are.
Now that we made `resolve_lifetimes` into a query, elision errors no
longer abort compilation, which affects some tests.
Also, remove `dep_graph_crosscontaminate_tables` -- there is no a path in
the dep-graph, though red-green handles it. The same scenario
is (correctly) tested by issue-42602.rs in any case.
This commit alters how we compile LLVM by default enabling the WebAssembly
backend. This then also adds the wasm32-unknown-unknown target to get compiled
on the `cross` builder and distributed through rustup. Tests are not yet enabled
for this target but that should hopefully be coming soon!
rustc_driver: expose a way to override query providers in CompileController.
This API has been a long-time coming and will probably become the main method for custom drivers (that is, binaries other than `rustc` itself that use `librustc_driver`) to adapt the compiler's behavior.
Allow overriding the TLS model
This PR adds the ability to override the default "global-dynamic" TLS model with a more specific one through a target json option or a command-line option. This allows for better code generation in certain situations.
This is similar to the `-ftls-model=` option in GCC and Clang.
DefaultImpl is a highly confusing name for what we now call auto impls,
as in `impl Send for ..`. The name auto impl is not formally decided
but for sanity anything is better than `DefaultImpl` which refers
neither to `default impl` nor to `impl Default`.
enable non-lexical lifetimes in the MIR borrow checker
This PR, joint work with @spastorino, fills out the NLL infrastructure and integrates it with the borrow checker. **Don't get too excited:** it includes still a number of hacks (the subtyping code is particularly hacky). However, it *does* kinda' work. =)
The final commit demonstrates this by including a test that -- with both the AST borrowck and MIR borrowck -- reports an error by default. But if you pass `-Znll`, you only get an error from the AST borrowck, demonstrating that the integration succeeds:
```
struct MyStruct {
field: String
}
fn main() {
let mut my_struct = MyStruct { field: format!("Hello") };
let value = &my_struct.field;
if value.is_empty() {
my_struct.field.push_str("Hello, world!");
//~^ ERROR cannot borrow (Ast)
}
}
```
incr.comp.: Implement compiler diagnostic persistence.
This PR implements storing and loading diagnostics that the compiler generates and thus allows for emitting warnings during incremental compilation without actually re-evaluating the thing the warning originally came from. It also lays some groundwork for storing and loading type information and MIR in the incr. comp. cache.
~~It is still work in progress:~~
- ~~There's still some documentation to be added.~~
- ~~The way anonymous queries are handled might lead to duplicated emissions of warnings. Not sure if there is a better way or how frequent such duplication would be in practice.~~
Diagnostic message duplication is addressed separately in #45519.
r? @nikomatsakis
