rustc_monomorphize/
lib.rs

1// tidy-alphabetical-start
2#![feature(array_windows)]
3#![feature(file_buffered)]
4#![feature(if_let_guard)]
5#![feature(impl_trait_in_assoc_type)]
6#![feature(let_chains)]
7#![warn(unreachable_pub)]
8// tidy-alphabetical-end
9
10use rustc_hir::lang_items::LangItem;
11use rustc_middle::query::TyCtxtAt;
12use rustc_middle::ty::adjustment::CustomCoerceUnsized;
13use rustc_middle::ty::{self, Ty};
14use rustc_middle::util::Providers;
15use rustc_middle::{bug, traits};
16use rustc_span::ErrorGuaranteed;
17
18mod collector;
19mod errors;
20mod mono_checks;
21mod partitioning;
22mod util;
23
24rustc_fluent_macro::fluent_messages! { "../messages.ftl" }
25
26fn custom_coerce_unsize_info<'tcx>(
27    tcx: TyCtxtAt<'tcx>,
28    source_ty: Ty<'tcx>,
29    target_ty: Ty<'tcx>,
30) -> Result<CustomCoerceUnsized, ErrorGuaranteed> {
31    let trait_ref = ty::TraitRef::new(
32        tcx.tcx,
33        tcx.require_lang_item(LangItem::CoerceUnsized, Some(tcx.span)),
34        [source_ty, target_ty],
35    );
36
37    match tcx
38        .codegen_select_candidate(ty::TypingEnv::fully_monomorphized().as_query_input(trait_ref))
39    {
40        Ok(traits::ImplSource::UserDefined(traits::ImplSourceUserDefinedData {
41            impl_def_id,
42            ..
43        })) => Ok(tcx.coerce_unsized_info(impl_def_id)?.custom_kind.unwrap()),
44        impl_source => {
45            bug!(
46                "invalid `CoerceUnsized` from {source_ty} to {target_ty}: impl_source: {:?}",
47                impl_source
48            );
49        }
50    }
51}
52
53pub fn provide(providers: &mut Providers) {
54    partitioning::provide(providers);
55    mono_checks::provide(providers);
56}