Try to reproduce ubsan issue

[MBkkt]

This function isn't marked as always inline, so inline or not highly depends on compiler options.
I think it doesn't work when not inlined.

So to check this is true or not, it just needs to run libunwind + libcxx + libcxxabi tests with undefined sanitizer.

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[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Valery Mironov (MBkkt)

Changes

This function isn't marked as always inline, so inline or not highly depends on compiler options.
I think it doesn't work when not inlined.

---

Full diff: https://github.com/llvm/llvm-project/pull/122389.diff

1 Files Affected:

• (modified) libcxx/include/typeinfo (+1-1)

diff --git a/libcxx/include/typeinfo b/libcxx/include/typeinfo
index 799c6ebd5ecbbf..e88de3ef35e89c 100644
--- a/libcxx/include/typeinfo
+++ b/libcxx/include/typeinfo
@@ -315,7 +315,7 @@ public:
 
   _LIBCPP_HIDE_FROM_ABI size_t hash_code() const _NOEXCEPT { return __impl::__hash(__type_name); }
 
-  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
+  _LIBCPP_HIDE_FROM_ABI _LIBCPP_NOINLINE _LIBCPP_CONSTEXPR_SINCE_CXX23 bool operator==(const type_info& __arg) const _NOEXCEPT {
     // When evaluated in a constant expression, both type infos simply can't come
     // from different translation units, so it is sufficient to compare their addresses.
     if (__libcpp_is_constant_evaluated()) {