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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug gcov-profile/97461] [11 Regression] allocate_gcov_kvp()
 deadlocks in firefox LTO+PGO build (overridden malloc() recursion)
Date: Thu, 29 Oct 2020 19:11:19 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D97461

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #18 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Formatting - one space after =3D rather than two.
Why do you need the __gcov_test_memory variable at all?
If you want to avoid optimizing away the malloc/free pair, just make it
volatile
- char *volatile p =3D malloc (16); free (p); or use a memory barrier in th=
ere.
Can the function be called from multiple threads concurrently?
I guess it isn't a big deal if malloc/free pair is called in each of them o=
nce,
but perhaps it should use __atomic_load_n and __atomic_store_n for the
malloc_initialized variable?=