This PR implements span quoting, allowing proc-macros to produce spans
pointing *into their own crate*. This is used by the unstable
`proc_macro::quote!` macro, allowing us to get error messages like this:
```
error[E0412]: cannot find type `MissingType` in this scope
--> $DIR/auxiliary/span-from-proc-macro.rs:37:20
|
LL | pub fn error_from_attribute(_args: TokenStream, _input: TokenStream) -> TokenStream {
| ----------------------------------------------------------------------------------- in this expansion of procedural macro `#[error_from_attribute]`
...
LL | field: MissingType
| ^^^^^^^^^^^ not found in this scope
|
::: $DIR/span-from-proc-macro.rs:8:1
|
LL | #[error_from_attribute]
| ----------------------- in this macro invocation
```
Here, `MissingType` occurs inside the implementation of the proc-macro
`#[error_from_attribute]`. Previosuly, this would always result in a
span pointing at `#[error_from_attribute]`
This will make many proc-macro-related error message much more useful -
when a proc-macro generates code containing an error, users will get an
error message pointing directly at that code (within the macro
definition), instead of always getting a span pointing at the macro
invocation site.
This is implemented as follows:
* When a proc-macro crate is being *compiled*, it causes the `quote!`
macro to get run. This saves all of the sapns in the input to `quote!`
into the metadata of *the proc-macro-crate* (which we are currently
compiling). The `quote!` macro then expands to a call to
`proc_macro::Span::recover_proc_macro_span(id)`, where `id` is an
opaque identifier for the span in the crate metadata.
* When the same proc-macro crate is *run* (e.g. it is loaded from disk
and invoked by some consumer crate), the call to
`proc_macro::Span::recover_proc_macro_span` causes us to load the span
from the proc-macro crate's metadata. The proc-macro then produces a
`TokenStream` containing a `Span` pointing into the proc-macro crate
itself.
The recursive nature of 'quote!' can be difficult to understand at
first. The file `src/test/ui/proc-macro/quote-debug.stdout` shows
the output of the `quote!` macro, which should make this eaier to
understand.
This PR also supports custom quoting spans in custom quote macros (e.g.
the `quote` crate). All span quoting goes through the
`proc_macro::quote_span` method, which can be called by a custom quote
macro to perform span quoting. An example of this usage is provided in
`src/test/ui/proc-macro/auxiliary/custom-quote.rs`
Custom quoting currently has a few limitations:
In order to quote a span, we need to generate a call to
`proc_macro::Span::recover_proc_macro_span`. However, proc-macros
support renaming the `proc_macro` crate, so we can't simply hardcode
this path. Previously, the `quote_span` method used the path
`crate::Span` - however, this only works when it is called by the
builtin `quote!` macro in the same crate. To support being called from
arbitrary crates, we need access to the name of the `proc_macro` crate
to generate a path. This PR adds an additional argument to `quote_span`
to specify the name of the `proc_macro` crate. Howver, this feels kind
of hacky, and we may want to change this before stabilizing anything
quote-related.
Additionally, using `quote_span` currently requires enabling the
`proc_macro_internals` feature. The builtin `quote!` macro
has an `#[allow_internal_unstable]` attribute, but this won't work for
custom quote implementations. This will likely require some additional
tricks to apply `allow_internal_unstable` to the span of
`proc_macro::Span::recover_proc_macro_span`.
Change param name (k to key and v to value) in std::env module
1. When I was reading code the ide displayed `k` and `v`, so I
thought it would be better to show key and value?
2. I noticed var method already uses `key` instead of `k` so it
is more consistent to use `key` instead of `k`?
Thanks
rustdoc: remove explicit boolean comparisons.
For boolean variables it's shorter and more readable to check the value directly, or negate it with `!`.
In a couple of cases I reordered an if/else pair because it made the initial `if` statement simpler.
An example of a style guide recommending this: https://airbnb.io/javascript/#comparison--shortcuts
r? `@GuillaumeGomez`
BTree: no longer copy keys and values before dropping them
When dropping BTreeMap or BTreeSet instances, keys-value pairs are up to now each copied and then dropped, at least according to source code. This is because the code for dropping and for iterators is shared.
This PR postpones the treatment of doomed key-value pairs from the intermediate functions `deallocating_next`(`_back`) to the last minute, so the we can drop the keys and values in place. According to the library/alloc benchmarks, this does make a difference, (and a positive difference with an `#[inline]` on `drop_key_val`). It does not change anything for #81444 though.
r? `@Mark-Simulacrum`
For boolean variables it's shorter and more readable to check the value
directly, or negate it with `!`.
In a couple of cases I reordered an if/else pair because it made the
initial `if` statement simpler.
Removed unused isType parameter from two functions.
At first you might think "why not just click through to the aliased
type?", but if a type alias instantiates all of the generic parameters
of the aliased type, then it can show layout info even though the
aliased type cannot (because we can't compute the layout of a generic
type). So I think it's still useful to show layout info for type
aliases.
Emit errors/warns on some wrong uses of rustdoc attributes
This PR adds a few diagnostics:
- error if conflicting `#[doc(inline)]`/`#[doc(no_inline)]` are found
- introduce the `invalid_doc_attributes` lint (warn-by-default) which triggers:
- if a crate-level attribute is used on a non-`crate` item
- if `#[doc(inline)]`/`#[doc(no_inline)]` is used on a non-`use` item
The code could probably be improved but I wanted to get feedback first. Also, some of those changes could be considered breaking changes, so I don't know what the procedure would be? ~~And finally, for the warnings, they are currently hard warnings, maybe it would be better to introduce a lint?~~ (EDIT: introduced the `invalid_doc_attributes` lint)
Closes#80275.
r? `@jyn514`
RELEASES.md: Use broken_intra_doc_links as an example, not nightly lint
`non_autolinks` has since been renamed and also was unstable at the time
this was written.
Show nicer error when an 'unstable fingerprints' error occurs
An example of the error produced by this PR:
```
error: internal compiler error: encountered incremental compilation error with evaluate_obligation(9f2ad55260c30262-c36667639674ad83)
|
= help: This is a known issue with the compiler. Run `cargo clean -p syn` or `cargo clean` to allow your project to compile
= note: Please follow the instructions below to create a bug report with the provided information
thread 'rustc' panicked at 'Found unstable fingerprints for evaluate_obligation(9f2ad55260c30262-c36667639674ad83): Ok(EvaluatedToOk)', /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:595:9
stack backtrace:
0: rust_begin_unwind
at /home/aaron/repos/rust/library/std/src/panicking.rs:493:5
1: std::panicking::begin_panic_fmt
at /home/aaron/repos/rust/library/std/src/panicking.rs:435:5
2: rustc_query_system::query::plumbing::incremental_verify_ich
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:595:9
3: rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:557:9
4: rustc_query_system::query::plumbing::try_execute_query::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:473:21
5: core::option::Option<T>::map
at /home/aaron/repos/rust/library/core/src/option.rs:487:29
6: rustc_query_system::query::plumbing::try_execute_query::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:471:13
7: stacker::maybe_grow
at /home/aaron/.cargo/registry/src/github.com-1ecc6299db9ec823/stacker-0.1.12/src/lib.rs:55:9
8: rustc_data_structures::stack::ensure_sufficient_stack
at /home/aaron/repos/rust/compiler/rustc_data_structures/src/stack.rs:16:5
9: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:169:17
10: rustc_middle::ty::context::tls::enter_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:50
11: rustc_middle::ty::context::tls::set_tlv
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1720:9
12: rustc_middle::ty::context::tls::enter_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:9
13: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:168:13
14: rustc_middle::ty::context::tls::with_related_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1780:13
15: rustc_middle::ty::context::tls::with_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:40
16: rustc_middle::ty::context::tls::with_context_opt
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1753:22
17: rustc_middle::ty::context::tls::with_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:9
18: rustc_middle::ty::context::tls::with_related_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1777:9
19: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:157:9
20: rustc_query_system::query::plumbing::try_execute_query
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:469:22
21: rustc_query_system::query::plumbing::get_query_impl
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:674:5
22: rustc_query_system::query::plumbing::get_query
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:785:9
23: <rustc_query_impl::Queries as rustc_middle::ty::query::QueryEngine>::evaluate_obligation
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:603:17
24: rustc_middle::ty::query::TyCtxtAt::evaluate_obligation
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/query/mod.rs:204:17
25: rustc_middle::ty::query::<impl rustc_middle::ty::context::TyCtxt>::evaluate_obligation
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/query/mod.rs:185:17
26: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation
at /home/aaron/repos/rust/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs:72:9
27: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::evaluate_obligation_no_overflow
at /home/aaron/repos/rust/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs:82:15
28: <rustc_infer::infer::InferCtxt as rustc_trait_selection::traits::query::evaluate_obligation::InferCtxtExt>::predicate_must_hold_modulo_regions
at /home/aaron/repos/rust/compiler/rustc_trait_selection/src/traits/query/evaluate_obligation.rs:58:9
29: rustc_trait_selection::traits::type_known_to_meet_bound_modulo_regions
at /home/aaron/repos/rust/compiler/rustc_trait_selection/src/traits/mod.rs:146:18
30: rustc_ty_utils::common_traits::is_item_raw::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_ty_utils/src/common_traits.rs:33:9
31: rustc_infer::infer::InferCtxtBuilder::enter
at /home/aaron/repos/rust/compiler/rustc_infer/src/infer/mod.rs:582:9
32: rustc_ty_utils::common_traits::is_item_raw
at /home/aaron/repos/rust/compiler/rustc_ty_utils/src/common_traits.rs:32:5
33: rustc_query_system::query::config::QueryVtable<CTX,K,V>::compute
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/config.rs:44:9
34: rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:544:67
35: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:77:46
36: rustc_middle::ty::context::tls::enter_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:50
37: rustc_middle::ty::context::tls::set_tlv
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1720:9
38: rustc_middle::ty::context::tls::enter_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:9
39: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:77:13
40: rustc_middle::ty::context::tls::with_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:40
41: rustc_middle::ty::context::tls::with_context_opt
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1753:22
42: rustc_middle::ty::context::tls::with_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:9
43: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:74:9
44: rustc_query_system::dep_graph::graph::DepGraph<K>::with_ignore
at /home/aaron/repos/rust/compiler/rustc_query_system/src/dep_graph/graph.rs:167:9
45: rustc_query_system::query::plumbing::load_from_disk_and_cache_in_memory
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:544:22
46: rustc_query_system::query::plumbing::try_execute_query::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:473:21
47: core::option::Option<T>::map
at /home/aaron/repos/rust/library/core/src/option.rs:487:29
48: rustc_query_system::query::plumbing::try_execute_query::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:471:13
49: stacker::maybe_grow
at /home/aaron/.cargo/registry/src/github.com-1ecc6299db9ec823/stacker-0.1.12/src/lib.rs:55:9
50: rustc_data_structures::stack::ensure_sufficient_stack
at /home/aaron/repos/rust/compiler/rustc_data_structures/src/stack.rs:16:5
51: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:169:17
52: rustc_middle::ty::context::tls::enter_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:50
53: rustc_middle::ty::context::tls::set_tlv
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1720:9
54: rustc_middle::ty::context::tls::enter_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:9
55: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:168:13
56: rustc_middle::ty::context::tls::with_related_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1780:13
57: rustc_middle::ty::context::tls::with_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:40
58: rustc_middle::ty::context::tls::with_context_opt
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1753:22
59: rustc_middle::ty::context::tls::with_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:9
60: rustc_middle::ty::context::tls::with_related_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1777:9
61: <rustc_query_impl::plumbing::QueryCtxt as rustc_query_system::query::QueryContext>::start_query
at /home/aaron/repos/rust/compiler/rustc_query_impl/src/plumbing.rs:157:9
62: rustc_query_system::query::plumbing::try_execute_query
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:469:22
63: rustc_query_system::query::plumbing::get_query_impl
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:674:5
64: rustc_query_system::query::plumbing::get_query
at /home/aaron/repos/rust/compiler/rustc_query_system/src/query/plumbing.rs:785:9
65: rustc_middle::ty::query::TyCtxtAt::is_unpin_raw
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/query/mod.rs:204:17
66: rustc_middle::ty::util::<impl rustc_middle::ty::TyS>::is_unpin
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/util.rs:727:38
67: rustc_middle::ty::layout::<impl rustc_target::abi::TyAndLayoutMethods<C> for &rustc_middle::ty::TyS>::pointee_info_at
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2341:32
68: rustc_target::abi::TyAndLayout<Ty>::pointee_info_at
at /home/aaron/repos/rust/compiler/rustc_target/src/abi/mod.rs:1164:9
69: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::new_internal::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2781:36
70: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::new_internal::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2840:17
71: rustc_target::abi::call::ArgAbi<Ty>::new
at /home/aaron/repos/rust/compiler/rustc_target/src/abi/call/mod.rs:457:53
72: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::new_internal::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2838:27
73: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::new_internal::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2870:32
74: core::iter::adapters::map::map_fold::{{closure}}
at /home/aaron/repos/rust/library/core/src/iter/adapters/map.rs:82:28
75: <core::iter::adapters::enumerate::Enumerate<I> as core::iter::traits::iterator::Iterator>::fold::enumerate::{{closure}}
at /home/aaron/repos/rust/library/core/src/iter/adapters/enumerate.rs:104:27
76: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
at /home/aaron/repos/rust/library/core/src/ops/function.rs:269:13
77: core::ops::function::impls::<impl core::ops::function::FnMut<A> for &mut F>::call_mut
at /home/aaron/repos/rust/library/core/src/ops/function.rs:269:13
78: core::iter::adapters::map::map_fold::{{closure}}
at /home/aaron/repos/rust/library/core/src/iter/adapters/map.rs:82:21
79: core::iter::traits::iterator::Iterator::fold
at /home/aaron/repos/rust/library/core/src/iter/traits/iterator.rs:2146:21
80: <core::iter::adapters::map::Map<I,F> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/map.rs:122:9
81: <core::iter::adapters::cloned::Cloned<I> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/cloned.rs:58:9
82: <core::iter::adapters::chain::Chain<A,B> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/chain.rs:119:19
83: <core::iter::adapters::chain::Chain<A,B> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/chain.rs:119:19
84: <core::iter::adapters::enumerate::Enumerate<I> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/enumerate.rs:110:9
85: <core::iter::adapters::map::Map<I,F> as core::iter::traits::iterator::Iterator>::fold
at /home/aaron/repos/rust/library/core/src/iter/adapters/map.rs:122:9
86: core::iter::traits::iterator::Iterator::for_each
at /home/aaron/repos/rust/library/core/src/iter/traits/iterator.rs:776:9
87: <alloc::vec::Vec<T,A> as alloc::vec::spec_extend::SpecExtend<T,I>>::spec_extend
at /home/aaron/repos/rust/library/alloc/src/vec/spec_extend.rs:40:17
88: <alloc::vec::Vec<T> as alloc::vec::spec_from_iter_nested::SpecFromIterNested<T,I>>::from_iter
at /home/aaron/repos/rust/library/alloc/src/vec/spec_from_iter_nested.rs:56:9
89: <alloc::vec::Vec<T> as alloc::vec::spec_from_iter::SpecFromIter<T,I>>::from_iter
at /home/aaron/repos/rust/library/alloc/src/vec/spec_from_iter.rs:36:9
90: <alloc::vec::Vec<T> as core::iter::traits::collect::FromIterator<T>>::from_iter
at /home/aaron/repos/rust/library/alloc/src/vec/mod.rs:2448:9
91: core::iter::traits::iterator::Iterator::collect
at /home/aaron/repos/rust/library/core/src/iter/traits/iterator.rs:1788:9
92: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::new_internal
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2864:19
93: <rustc_target::abi::call::FnAbi<&rustc_middle::ty::TyS> as rustc_middle::ty::layout::FnAbiExt<C>>::of_instance
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/layout.rs:2670:9
94: rustc_codegen_llvm::mono_item::<impl rustc_codegen_ssa::traits::declare::PreDefineMethods for rustc_codegen_llvm::context::CodegenCx>::predefine_fn
at /home/aaron/repos/rust/compiler/rustc_codegen_llvm/src/mono_item.rs:57:22
95: <rustc_middle::mir::mono::MonoItem as rustc_codegen_ssa::mono_item::MonoItemExt>::predefine
at /home/aaron/repos/rust/compiler/rustc_codegen_ssa/src/mono_item.rs:76:17
96: rustc_codegen_llvm::base::compile_codegen_unit::module_codegen
at /home/aaron/repos/rust/compiler/rustc_codegen_llvm/src/base.rs:122:17
97: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_query_system/src/dep_graph/graph.rs:235:62
98: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:77:46
99: rustc_middle::ty::context::tls::enter_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:50
100: rustc_middle::ty::context::tls::set_tlv
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1720:9
101: rustc_middle::ty::context::tls::enter_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:9
102: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:77:13
103: rustc_middle::ty::context::tls::with_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:40
104: rustc_middle::ty::context::tls::with_context_opt
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1753:22
105: rustc_middle::ty::context::tls::with_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1764:9
106: rustc_middle::dep_graph::<impl rustc_query_system::dep_graph::DepKind for rustc_middle::dep_graph::dep_node::DepKind>::with_deps
at /home/aaron/repos/rust/compiler/rustc_middle/src/dep_graph/mod.rs:74:9
107: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task_impl
at /home/aaron/repos/rust/compiler/rustc_query_system/src/dep_graph/graph.rs:235:26
108: rustc_query_system::dep_graph::graph::DepGraph<K>::with_task
at /home/aaron/repos/rust/compiler/rustc_query_system/src/dep_graph/graph.rs:205:9
109: rustc_codegen_llvm::base::compile_codegen_unit
at /home/aaron/repos/rust/compiler/rustc_codegen_llvm/src/base.rs:103:9
110: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_ssa::traits::backend::ExtraBackendMethods>::compile_codegen_unit
at /home/aaron/repos/rust/compiler/rustc_codegen_llvm/src/lib.rs:109:9
111: rustc_codegen_ssa::base::codegen_crate
at /home/aaron/repos/rust/compiler/rustc_codegen_ssa/src/base.rs:655:38
112: <rustc_codegen_llvm::LlvmCodegenBackend as rustc_codegen_ssa::traits::backend::CodegenBackend>::codegen_crate
at /home/aaron/repos/rust/compiler/rustc_codegen_llvm/src/lib.rs:270:18
113: rustc_interface::passes::start_codegen::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/passes.rs:1021:9
114: rustc_data_structures::profiling::VerboseTimingGuard::run
at /home/aaron/repos/rust/compiler/rustc_data_structures/src/profiling.rs:573:9
115: rustc_session::utils::<impl rustc_session::session::Session>::time
at /home/aaron/repos/rust/compiler/rustc_session/src/utils.rs:16:9
116: rustc_interface::passes::start_codegen
at /home/aaron/repos/rust/compiler/rustc_interface/src/passes.rs:1020:19
117: rustc_interface::queries::Queries::ongoing_codegen::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/queries.rs:296:20
118: rustc_interface::passes::QueryContext::enter::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/passes.rs:755:42
119: rustc_middle::ty::context::tls::enter_context::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:50
120: rustc_middle::ty::context::tls::set_tlv
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1720:9
121: rustc_middle::ty::context::tls::enter_context
at /home/aaron/repos/rust/compiler/rustc_middle/src/ty/context.rs:1736:9
122: rustc_interface::passes::QueryContext::enter
at /home/aaron/repos/rust/compiler/rustc_interface/src/passes.rs:755:9
123: rustc_interface::queries::Queries::ongoing_codegen::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/queries.rs:287:13
124: rustc_interface::queries::Query<T>::compute
at /home/aaron/repos/rust/compiler/rustc_interface/src/queries.rs:40:28
125: rustc_interface::queries::Queries::ongoing_codegen
at /home/aaron/repos/rust/compiler/rustc_interface/src/queries.rs:285:9
126: rustc_driver::run_compiler::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_driver/src/lib.rs:442:13
127: rustc_interface::queries::<impl rustc_interface::interface::Compiler>::enter
at /home/aaron/repos/rust/compiler/rustc_interface/src/queries.rs:428:19
128: rustc_driver::run_compiler::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_driver/src/lib.rs:337:22
129: rustc_interface::interface::create_compiler_and_run::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/interface.rs:208:13
130: rustc_span::with_source_map
at /home/aaron/repos/rust/compiler/rustc_span/src/lib.rs:788:5
131: rustc_interface::interface::create_compiler_and_run
at /home/aaron/repos/rust/compiler/rustc_interface/src/interface.rs:202:5
132: rustc_interface::interface::run_compiler::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/interface.rs:224:12
133: rustc_interface::util::setup_callbacks_and_run_in_thread_pool_with_globals::{{closure}}::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/util.rs:155:13
134: scoped_tls::ScopedKey<T>::set
at /home/aaron/.cargo/registry/src/github.com-1ecc6299db9ec823/scoped-tls-1.0.0/src/lib.rs:137:9
135: rustc_span::with_session_globals
at /home/aaron/repos/rust/compiler/rustc_span/src/lib.rs:105:5
136: rustc_interface::util::setup_callbacks_and_run_in_thread_pool_with_globals::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/util.rs:153:9
137: rustc_interface::util::scoped_thread::{{closure}}
at /home/aaron/repos/rust/compiler/rustc_interface/src/util.rs:128:24
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
error: internal compiler error: unexpected panic
note: the compiler unexpectedly panicked. this is a bug.
note: we would appreciate a bug report: https://github.com/rust-lang/rust/issues/new?labels=C-bug%2C+I-ICE%2C+T-compiler&template=ice.md
note: rustc 1.54.0-dev running on x86_64-unknown-linux-gnu
note: compiler flags: -C opt-level=3 -C embed-bitcode=no -C incremental --crate-type lib
note: some of the compiler flags provided by cargo are hidden
query stack during panic:
#0 [evaluate_obligation] evaluating trait selection obligation `quote::Tokens: std::marker::Unpin`
#1 [is_unpin_raw] computing whether `quote::Tokens` is `Unpin`
end of query stack
error: aborting due to previous error
error: could not compile `syn`
To learn more, run the command again with --verbose.
```
I've left in the panic and ICE following the pretty error, so that we still have all of the debug information available in a bug report.
This message can be reproduced by cloning the repository `https://github.com/Aaron1011/syn-crash`, and running the following shell script (with a `rustup override` set in the directory):
```
set -xe
cargo clean -p syn
cargo clean --release -p syn
git checkout minimize
cargo build --release -j 1
git checkout minimize-change
cargo build --release -j 1
```
r? ``@Mark-Simulacrum``
Aaron Hill