Auto merge of #136000 - matthiaskrgr:rollup-j6ge32r, r=matthiaskrgr

Rollup of 6 pull requests

Successful merges:

 - #135873 (coverage: Prepare for upcoming changes to counter creation)
 - #135926 (Implement `needs-subprocess` directive, and cleanup a bunch of tests to use `needs-{subprocess,threads}`)
 - #135950 (Tidy Python improvements)
 - #135956 (Make `Vec::pop_if` a bit more presentable)
 - #135966 ([AIX] Allow different sized load and store in `tests/assembly/powerpc64-struct-abi.rs`)
 - #135983 (Doc difference between extend and extend_from_slice)

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

1 files changed, 3 insertions, 9 deletions

diff --git a/compiler/rustc_mir_transform/src/coverage/query.rs b/compiler/rustc_mir_transform/src/coverage/query.rs
index 3e7cf8541c2..5e7b46182dc 100644
--- a/compiler/rustc_mir_transform/src/coverage/query.rs
+++ b/compiler/rustc_mir_transform/src/coverage/query.rs
@@ -87,15 +87,9 @@ fn coverage_attr_on(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
 fn coverage_ids_info<'tcx>(
     tcx: TyCtxt<'tcx>,
     instance_def: ty::InstanceKind<'tcx>,
-) -> CoverageIdsInfo {
+) -> Option<CoverageIdsInfo> {
     let mir_body = tcx.instance_mir(instance_def);
-
-    let Some(fn_cov_info) = mir_body.function_coverage_info.as_deref() else {
-        return CoverageIdsInfo {
-            counters_seen: DenseBitSet::new_empty(0),
-            zero_expressions: DenseBitSet::new_empty(0),
-        };
-    };
+    let fn_cov_info = mir_body.function_coverage_info.as_deref()?;
 
     let mut counters_seen = DenseBitSet::new_empty(fn_cov_info.num_counters);
     let mut expressions_seen = DenseBitSet::new_filled(fn_cov_info.expressions.len());
@@ -129,7 +123,7 @@ fn coverage_ids_info<'tcx>(
     let zero_expressions =
         identify_zero_expressions(fn_cov_info, &counters_seen, &expressions_seen);
 
-    CoverageIdsInfo { counters_seen, zero_expressions }
+    Some(CoverageIdsInfo { counters_seen, zero_expressions })
 }
 
 fn all_coverage_in_mir_body<'a, 'tcx>(