Auto merge of #141133 - matthiaskrgr:rollup-u8ndxyz, r=matthiaskrgr

Rollup of 9 pull requests

Successful merges:

 - #135808 (Implement Display for ``rustc_target::callconv::Conv``)
 - #137432 (Add as_ascii_unchecked() methods to char, u8, and str)
 - #139103 (deduplicate abort implementations)
 - #140917 (checktools.sh: fix bashism)
 - #141035 (turn lld warning on old gccs into info log)
 - #141118 (Enable rust-analyzer to go from query definition to the corresponding provider field)
 - #141121 (Only select true errors in `impossible_predicates`)
 - #141125 (check coroutines with `TypingMode::Borrowck` to avoid cyclic reasoning)
 - #141131 (Make some `match`es slightly more ergonomic in `librustdoc`)

r? `@ghost`
`@rustbot` modify labels: rollup

1 files changed, 13 insertions, 7 deletions

diff --git a/compiler/rustc_hir_analysis/src/check/check.rs b/compiler/rustc_hir_analysis/src/check/check.rs
index f92b2aea160..da94331aa26 100644
--- a/compiler/rustc_hir_analysis/src/check/check.rs
+++ b/compiler/rustc_hir_analysis/src/check/check.rs
@@ -1754,17 +1754,19 @@ pub(super) fn check_coroutine_obligations(
     debug!(?typeck_results.coroutine_stalled_predicates);
 
     let mode = if tcx.next_trait_solver_globally() {
-        TypingMode::post_borrowck_analysis(tcx, def_id)
+        // This query is conceptually between HIR typeck and
+        // MIR borrowck. We use the opaque types defined by HIR
+        // and ignore region constraints.
+        TypingMode::borrowck(tcx, def_id)
     } else {
         TypingMode::analysis_in_body(tcx, def_id)
     };
 
-    let infcx = tcx
-        .infer_ctxt()
-        // typeck writeback gives us predicates with their regions erased.
-        // As borrowck already has checked lifetimes, we do not need to do it again.
-        .ignoring_regions()
-        .build(mode);
+    // Typeck writeback gives us predicates with their regions erased.
+    // We only need to check the goals while ignoring lifetimes to give good
+    // error message and to avoid breaking the assumption of `mir_borrowck`
+    // that all obligations already hold modulo regions.
+    let infcx = tcx.infer_ctxt().ignoring_regions().build(mode);
 
     let ocx = ObligationCtxt::new_with_diagnostics(&infcx);
     for (predicate, cause) in &typeck_results.coroutine_stalled_predicates {
@@ -1785,6 +1787,10 @@ pub(super) fn check_coroutine_obligations(
             let key = infcx.resolve_vars_if_possible(key);
             sanity_check_found_hidden_type(tcx, key, hidden_type)?;
         }
+    } else {
+        // We're not checking region constraints here, so we can simply drop the
+        // added opaque type uses in `TypingMode::Borrowck`.
+        let _ = infcx.take_opaque_types();
     }
 
     Ok(())