[libcxx] [llvm] [ASan][libc++] Turn on ASan annotations for short strings (PR #79049)

[Vitaly Buka via llvm-commits]

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@@ -482,6 +482,9 @@ class Value {
   friend class Object;
 
   template <typename T, typename... U> void create(U &&... V) {
+#ifndef _LIBCPP_HAS_NO_ASAN
+    __asan_unpoison_memory_region(&Union, sizeof(T));
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vitalybuka wrote:

This one needs comment. This unpoisoning looks very random

https://github.com/llvm/llvm-project/pull/79049