From d7cecd3db24e3905a39f458e9202016a5685579a Mon Sep 17 00:00:00 2001
From: Ben Kimock <kimockb@gmail.com>
Date: Wed, 15 Nov 2023 19:16:06 -0500
Subject: [PATCH] Let Miri see the AllocId for all TyCtxt allocations

---
 compiler/rustc_middle/src/mir/interpret/mod.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/rustc_middle/src/mir/interpret/mod.rs b/compiler/rustc_middle/src/mir/interpret/mod.rs
index e360fb3eaaf..b87c6885e04 100644
--- a/compiler/rustc_middle/src/mir/interpret/mod.rs
+++ b/compiler/rustc_middle/src/mir/interpret/mod.rs
@@ -525,6 +525,13 @@ impl<'tcx> TyCtxt<'tcx> {
         self.alloc_map.lock().reserve()
     }
 
+    /// Miri's provenance GC needs to see all live allocations. The interpreter manages most
+    /// allocations but some are managed by [`TyCtxt`] and without this method the interpreter
+    /// doesn't know their [`AllocId`]s are in use.
+    pub fn iter_allocs<F: FnMut(AllocId)>(self, func: F) {
+        self.alloc_map.lock().alloc_map.keys().copied().for_each(func)
+    }
+
     /// Reserves a new ID *if* this allocation has not been dedup-reserved before.
     /// Should only be used for "symbolic" allocations (function pointers, vtables, statics), we
     /// don't want to dedup IDs for "real" memory!