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+# Phase 6 Pre-Audit: Single-Threaded Invariant and Stub Locations
+
+## Audit Results
+
+- **sched_meet_host_selection stub confirmed** at `src/scheduler/src/resource.c:127-131`
+  - Declaration: `src/scheduler/include/scheduler.h:111`
+  - Call site: `src/scheduler/src/resource.c:368` (within sched_try_alloc_on_host_)
+  - Stub body: returns 1 unconditionally
+
+- **Allocator-thread-only invariant confirmed**: Single `while(1)` loop in `src/scheduler/src/main.c:119`
+  - `sched_begin_session()` at line 121
+  - `sched_go()` at line 122
+  - `sched_end_session()` at line 161
+  - All three calls executed sequentially in the same thread context
+
+- **eval_select_simple signature confirmed**: `int eval_select_simple(const xce_select_node_t* root, const host_eval_ctx_t* host)`
+  - Declaration: `src/include/resreq.h:110-111`
+  - Definition: `src/lib/xce_select.c:558`
+  - Returns: 1 (match), 0 (no match), negative (error)
+
+No unexpected references to `sched_meet_host_selection`, `eval_select`, `alloc_thread`, or `sched_session` found in scheduler source.