diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs
index 5510bb0257e34..0aaccaed41667 100644
--- a/library/core/src/slice/mod.rs
+++ b/library/core/src/slice/mod.rs
@@ -2204,6 +2204,8 @@ impl<T> [T] {
             } else if cmp == Greater {
                 right = mid;
             } else {
+                // SAFETY: same as the `get_unchecked` above
+                unsafe { crate::intrinsics::assume(mid < self.len()) };
                 return Ok(mid);
             }
 
diff --git a/src/test/codegen/binary-search-index-no-bound-check.rs b/src/test/codegen/binary-search-index-no-bound-check.rs
new file mode 100644
index 0000000000000..110d1d55626f1
--- /dev/null
+++ b/src/test/codegen/binary-search-index-no-bound-check.rs
@@ -0,0 +1,19 @@
+// min-llvm-version: 11.0.0
+// compile-flags: -O
+// ignore-debug: the debug assertions get in the way
+#![crate_type = "lib"]
+
+// Make sure no bounds checks are emitted when slicing or indexing
+// with an index from `binary_search`.
+
+// CHECK-LABEL: @binary_search_index_no_bounds_check
+#[no_mangle]
+pub fn binary_search_index_no_bounds_check(s: &[u8]) -> u8 {
+    // CHECK-NOT: panic
+    // CHECK-NOT: slice_index_len_fail
+    if let Ok(idx) = s.binary_search(&b'\\') {
+        s[idx]
+    } else {
+        42
+    }
+}