- Move the type parameter from `encode` and `decode` methods to
the trait.
- Remove `UseSpecialized(En|De)codable` traits.
- Remove blanket impls for references.
- Add `RefDecodable` trait to allow deserializing to arena-allocated
references safely.
- Remove ability to (de)serialize HIR.
- Create proc-macros `(Ty)?(En|De)codable` to help implement these new
traits.
Avoid deleting temporary files on error
Previously if the compiler error'd, fatally, then temporary directories which
should be preserved by -Csave-temps would be deleted due to fatal compiler
errors being implemented as panics.
cc @infinity0
(Hopefully) fixes#75275, but I haven't tested
Previously if the compiler error'd, fatally, then temporary directories which
should be preserved by -Csave-temps would be deleted due to fatal compiler
errors being implemented as panics.
Prevent compiler stack overflow for deeply recursive code
I was unable to write a test that
1. runs in under 1s
2. overflows on my machine without this patch
The following reproduces the issue, but I don't think it's sensible to include a test that takes 30s to compile. We can now easily squash newly appearing overflows by the strategic insertion of calls to `ensure_sufficient_stack`.
```rust
// compile-pass
#![recursion_limit="1000000"]
macro_rules! chain {
(EE $e:expr) => {$e.sin()};
(RECURSE $i:ident $e:expr) => {chain!($i chain!($i chain!($i chain!($i $e))))};
(Z $e:expr) => {chain!(RECURSE EE $e)};
(Y $e:expr) => {chain!(RECURSE Z $e)};
(X $e:expr) => {chain!(RECURSE Y $e)};
(A $e:expr) => {chain!(RECURSE X $e)};
(B $e:expr) => {chain!(RECURSE A $e)};
(C $e:expr) => {chain!(RECURSE B $e)};
// causes overflow on x86_64 linux
// less than 1 second until overflow on test machine
// after overflow has been fixed, takes 30s to compile :/
(D $e:expr) => {chain!(RECURSE C $e)};
(E $e:expr) => {chain!(RECURSE D $e)};
(F $e:expr) => {chain!(RECURSE E $e)};
// more than 10 seconds
(G $e:expr) => {chain!(RECURSE F $e)};
(H $e:expr) => {chain!(RECURSE G $e)};
(I $e:expr) => {chain!(RECURSE H $e)};
(J $e:expr) => {chain!(RECURSE I $e)};
(K $e:expr) => {chain!(RECURSE J $e)};
(L $e:expr) => {chain!(RECURSE L $e)};
}
fn main() {
let x = chain!(D 42.0_f32);
}
```
fixes#55471fixes#41884fixes#40161fixes#34844fixes#32594
cc @alexcrichton @rust-lang/compiler
I looked at all code that checks the recursion limit and inserted stack growth calls where appropriate.
We anticipate this to have uses in all sorts of crates and keeping it in
`rustc_data_structures` enables access to it from more locations without
necessarily pulling in the large `librustc` crate.
The single dependency on queries (QueryName) can be fairly easily
abstracted via a trait and this further decouples Session from librustc
(the primary goal).
Now that procedural macros no longer link transitively to libsyntax,
this shouldn't be needed any more! This commit is an experiment in
removing all dynamic libraries from rustc except for librustc_driver
itself. Let's see how far we can get with that!
