[llvm] Pass std::initializer_list by value to ArrayRef constructor. (PR #113590)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-adt

Author: Haojian Wu (hokein)

<details>
<summary>Changes</summary>

The std::initializer_list is a lightweight object, it is passed by value in general.

This would also avoid a false positive when adding the lifetimebound annotation (#<!-- -->113547)

```
ArrayRef<int> foo(std::initializer_list<int> list) {
  return ArrayRef<int>(list);
}
```

---
Full diff: https://github.com/llvm/llvm-project/pull/113590.diff


1 Files Affected:

- (modified) llvm/include/llvm/ADT/ArrayRef.h (+1-1) 


``````````diff
diff --git a/llvm/include/llvm/ADT/ArrayRef.h b/llvm/include/llvm/ADT/ArrayRef.h
index d9897320ce091a..bf6b55923b84ba 100644
--- a/llvm/include/llvm/ADT/ArrayRef.h
+++ b/llvm/include/llvm/ADT/ArrayRef.h
@@ -113,7 +113,7 @@ namespace llvm {
 #pragma GCC diagnostic push
 #pragma GCC diagnostic ignored "-Winit-list-lifetime"
 #endif
-    constexpr /*implicit*/ ArrayRef(const std::initializer_list<T> &Vec)
+    constexpr /*implicit*/ ArrayRef(std::initializer_list<T> Vec)
         : Data(Vec.begin() == Vec.end() ? (T *)nullptr : Vec.begin()),
           Length(Vec.size()) {}
 #if LLVM_GNUC_PREREQ(9, 0, 0)

``````````

</details>


https://github.com/llvm/llvm-project/pull/113590