[Bug sanitizer/64265] [5 Regression] r217669 broke tsan

[dvyukov at google dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64265

--- Comment #11 from Dmitry Vyukov <dvyukov at google dot com> ---
>Doing it in gimplify_function_tree is pretty straightforward

That's good!

>So, the question is just if you want to do it that way...

Kostya, can you say anything about llvm? On the tsan issue you said:
"We'll need a kind of RAII for tsan entry/exit hooks. When we are adding tsan
instrumentation, we need to create a fake class object with a ctor and dtor."

Which suggests that you wanted to do it in a similar way in llvm.

If we decide to it this way in both compilers, then no support in runtime is
required, and gcc can well implement it ahead of llvm.