diff --git a/src/libcore/intrinsics.rs b/src/libcore/intrinsics.rs
index aff36aba01f..56e45c3695f 100644
--- a/src/libcore/intrinsics.rs
+++ b/src/libcore/intrinsics.rs
@@ -1333,7 +1333,6 @@ pub(crate) fn is_aligned_and_not_null<T>(ptr: *const T) -> bool {
 
 /// Checks whether the regions of memory starting at `src` and `dst` of size
 /// `count * size_of::<T>()` overlap.
-#[cfg(not(miri))] // Cannot compare with `>` across allocations in Miri
 fn overlaps<T>(src: *const T, dst: *const T, count: usize) -> bool {
     let src_usize = src as usize;
     let dst_usize = dst as usize;
@@ -1438,7 +1437,6 @@ pub unsafe fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize) {
 
     debug_assert!(is_aligned_and_not_null(src), "attempt to copy from unaligned or null pointer");
     debug_assert!(is_aligned_and_not_null(dst), "attempt to copy to unaligned or null pointer");
-    #[cfg(not(miri))]
     debug_assert!(!overlaps(src, dst, count), "attempt to copy to overlapping memory");
     copy_nonoverlapping(src, dst, count)
 }
diff --git a/src/tools/miri b/src/tools/miri
index b269bb07078..7ef40979157 160000
--- a/src/tools/miri
+++ b/src/tools/miri
@@ -1 +1 @@
-Subproject commit b269bb07078446c9c153e0f2acaf83bf8f19b935
+Subproject commit 7ef40979157b4117faa52bbe79ec144ebd45b0e3