From 353f7d539ae628a46ecfa1c316d963633e17e780 Mon Sep 17 00:00:00 2001
From: Ralf Jung <post@ralfj.de>
Date: Thu, 4 Aug 2022 09:55:18 -0400
Subject: [PATCH] add special exception for std_miri_test crate to call
 std-only functions

---
 src/helpers.rs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/helpers.rs b/src/helpers.rs
index 220347ff1b9..7c9f8740eb4 100644
--- a/src/helpers.rs
+++ b/src/helpers.rs
@@ -803,7 +803,12 @@ fn frame_in_std(&self) -> bool {
         // Fall back to the instance of the function itself.
         let instance = instance.unwrap_or(frame.instance);
         // Now check if this is in the same crate as start_fn.
-        this.tcx.def_path(instance.def_id()).krate == this.tcx.def_path(start_fn).krate
+        // As a special exception we also allow unit tests from
+        // <https://github.com/rust-lang/miri-test-libstd/tree/master/std_miri_test> to call these
+        // shims.
+        let frame_crate = this.tcx.def_path(instance.def_id()).krate;
+        frame_crate == this.tcx.def_path(start_fn).krate
+            || this.tcx.crate_name(frame_crate).as_str() == "std_miri_test"
     }
 
     /// Handler that should be called when unsupported functionality is encountered.