[libc++][ASan] Fix std::basic_string trait type

[AdvenamTacet]

Addresses the comment: #79536 (comment)

Changes the type to void instead of false_type.

The value is used here:

llvm-project/libcxx/include/__type_traits/is_trivially_relocatable.h

Lines 35 to 38 in 6f1013a

	template <class _Tp>
	struct __libcpp_is_trivially_relocatable<_Tp,
	__enable_if_t<is_same<_Tp, typename _Tp::__trivially_relocatable>::value> >
	: true_type {};

[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Tacet (AdvenamTacet)

Changes

Addresses comment: #79536 (comment)

Changes type to void instead of false_type.

The value is used here:

https://github.com/llvm/llvm-project/blob/main/libcxx/include/__type_traits/is_trivially_relocatable.h#L35-L38

---

Full diff: https://github.com/llvm/llvm-project/pull/91590.diff

1 Files Affected:

• (modified) libcxx/include/string (+2-2)

diff --git a/libcxx/include/string b/libcxx/include/string
index 8f629d8bf13c8..1db803e822d72 100644
--- a/libcxx/include/string
+++ b/libcxx/include/string
@@ -741,8 +741,8 @@ public:
   // is kept inside objects memory (short string optimization), instead of in allocated
   // external memory. In such cases, the destructor is responsible for unpoisoning
   // the memory to avoid triggering false positives.
-  // Therefore it's crucial to ensure the destructor is called
-  using __trivially_relocatable = false_type;
+  // Therefore it's crucial to ensure the destructor is called.
+  using __trivially_relocatable = void;
 #else
   using __trivially_relocatable = __conditional_t<
       __libcpp_is_trivially_relocatable<allocator_type>::value && __libcpp_is_trivially_relocatable<pointer>::value,