Auto merge of #67953 - cjgillot:split_infer, r=Zoxc

Split librustc::{traits,infer} to a separate crate rustc_infer

This is still very much work in progress.
Three functions are between dimensions (at the end of `rustc::traits`), waiting for some dependency breaking scheme.
Please tell me if the approach seems sound, and how you would like to split this PR up.

The formatting is deliberately off, to ease rebasing.

cc #65031

4 files changed, 5 insertions, 4 deletions

diff --git a/src/librustdoc/clean/auto_trait.rs b/src/librustdoc/clean/auto_trait.rs
index 8edd0591c85..289923b45e6 100644
--- a/src/librustdoc/clean/auto_trait.rs
+++ b/src/librustdoc/clean/auto_trait.rs
@@ -1,7 +1,7 @@
-use rustc::traits::auto_trait::{self, AutoTraitResult};
 use rustc::ty::{self, Region, RegionVid, TypeFoldable};
 use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
+use rustc_infer::traits::auto_trait::{self, AutoTraitResult};
 
 use std::fmt::Debug;
 
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs
index 288446b6219..f7968bf7722 100644
--- a/src/librustdoc/clean/blanket_impl.rs
+++ b/src/librustdoc/clean/blanket_impl.rs
@@ -1,9 +1,9 @@
-use rustc::infer::InferOk;
-use rustc::traits;
 use rustc::ty::subst::Subst;
 use rustc::ty::{ToPredicate, WithConstness};
 use rustc_hir as hir;
 use rustc_hir::def_id::LOCAL_CRATE;
+use rustc_infer::infer::{InferOk, TyCtxtInferExt};
+use rustc_infer::traits;
 use rustc_span::DUMMY_SP;
 
 use super::*;
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 87edc88611f..ee432647084 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -9,7 +9,6 @@ mod simplify;
 pub mod types;
 pub mod utils;
 
-use rustc::infer::region_constraints::{Constraint, RegionConstraintData};
 use rustc::middle::lang_items;
 use rustc::middle::resolve_lifetime as rl;
 use rustc::middle::stability;
@@ -22,6 +21,7 @@ use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
 use rustc_hir::def_id::{CrateNum, DefId, CRATE_DEF_INDEX};
 use rustc_index::vec::{Idx, IndexVec};
+use rustc_infer::infer::region_constraints::{Constraint, RegionConstraintData};
 use rustc_mir::const_eval::is_min_const_fn;
 use rustc_span::hygiene::MacroKind;
 use rustc_span::symbol::{kw, sym};
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 4e0a2d94274..eab88b7165d 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -26,6 +26,7 @@ extern crate rustc_expand;
 extern crate rustc_feature;
 extern crate rustc_hir;
 extern crate rustc_index;
+extern crate rustc_infer;
 extern crate rustc_interface;
 extern crate rustc_lexer;
 extern crate rustc_lint;