[libcxx-commits] [libcxx] [libc++] Fix possible out of range access in bitset (PR #121348)

[Louis Dionne via libcxx-commits]

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@@ -487,15 +531,20 @@ protected:
   _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool any() const _NOEXCEPT;
 
   _LIBCPP_HIDE_FROM_ABI size_t __hash_code() const _NOEXCEPT;
+
+private:
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long __to_ulong(false_type) const;
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long __to_ulong(true_type) const;
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long __to_ullong(false_type) const;
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 unsigned long long __to_ullong(true_type) const;
 };
 
 template <size_t _Size>
 inline _LIBCPP_CONSTEXPR __bitset<1, _Size>::__bitset() _NOEXCEPT : __first_(0) {}
 
 template <size_t _Size>
 inline _LIBCPP_CONSTEXPR __bitset<1, _Size>::__bitset(unsigned long long __v) _NOEXCEPT
-    : __first_(_Size == __bits_per_word ? static_cast<__storage_type>(__v)
-                                        : static_cast<__storage_type>(__v) & ((__storage_type(1) << _Size) - 1)) {}
+    : __first_(_Size == __bits_per_word ? static_cast<__storage_type>(__v) : static_cast<__storage_type>(__v)) {}
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ldionne wrote:

Is there a bug report against GCC for this? If so, let's link it from here, otherwise, can you file one against GCC?

https://github.com/llvm/llvm-project/pull/121348