[libcxx-commits] [libcxx] Add exception guard for constructor vector(n, x, a) (PR #113086)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libcxx

Author: None (winner245)

<details>
<summary>Changes</summary>

Added exception guard to the `vector(n, x, a)` constructor to enhance exception safety. This change ensures that the `vector(n, x, a)` constructor is consistent with other constructors, such as  `vector(n)`, `vector(n, x)`, `vector(n, a)`, in terms of exception safety.

---
Full diff: https://github.com/llvm/llvm-project/pull/113086.diff


1 Files Affected:

- (modified) libcxx/include/vector (+2) 


``````````diff
diff --git a/libcxx/include/vector b/libcxx/include/vector
index dc31f31838264c..700cb51f41eeb2 100644
--- a/libcxx/include/vector
+++ b/libcxx/include/vector
@@ -487,10 +487,12 @@ public:
   _LIBCPP_CONSTEXPR_SINCE_CXX20 _LIBCPP_HIDE_FROM_ABI
   vector(size_type __n, const value_type& __x, const allocator_type& __a)
       : __alloc_(__a) {
+    auto __guard = std::__make_exception_guard(__destroy_vector(*this));
     if (__n > 0) {
       __vallocate(__n);
       __construct_at_end(__n, __x);
     }
+    __guard.__complete();
   }
 
   template <class _InputIterator,

``````````

</details>


https://github.com/llvm/llvm-project/pull/113086