Sanitizer KCFI (Kernel Control Flow Integrity) reports Illegal instruction in libfabric.

[kjkozlowski]

Describe the bug
Sanitizer KCFI (Kernel Control Flow Integrity) reports Illegal instruction in libfabric.

To Reproduce
Checkout repository https://github.com/kjkozlowski/rxm_reproducer.

Output

Thread 2 "reproducer" received signal SIGILL, Illegal instruction.
[Switching to Thread 0x7ffff76f4640 (LWP 2056319)]
0x0000555555560b44 in fi_domain (fabric=0x7ffff00e4b90, info=0x7ffff00e8820, domain=0x7ffff76f3d28, context=0x0) at /mnt/kcfi/third_party/libfabric/include/rdma/fi_domain.h:362
362             return fabric->ops->domain(fabric, info, domain, context);
(gdb) bt
#0  0x0000555555560b44 in fi_domain (fabric=0x7ffff00e4b90, info=0x7ffff00e8820, domain=0x7ffff76f3d28, context=0x0) at /mnt/kcfi/third_party/libfabric/include/rdma/fi_domain.h:362
#1  0x000055555555fe5c in main::$_0::operator() (this=0x555555580748) at /mnt/kcfi/main.cpp:146
#2  0x000055555555fd55 in std::__invoke_impl<void, main::$_0> (__f=...) at /usr/lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/invoke.h:61
#3  0x000055555555fd15 in std::__invoke<main::$_0> (__fn=...) at /usr/lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/invoke.h:96
#4  0x000055555555fced in std::thread::_Invoker<std::tuple<main::$_0> >::_M_invoke<0ul> (this=0x555555580748) at /usr/lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/std_thread.h:279
#5  0x000055555555fcc5 in std::thread::_Invoker<std::tuple<main::$_0> >::operator() (this=0x555555580748) at /usr/lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/std_thread.h:286
#6  0x000055555555fc19 in std::thread::_State_impl<std::thread::_Invoker<std::tuple<main::$_0> > >::_M_run (this=0x555555580740) at /usr/lib/gcc/x86_64-linux-gnu/12/../../../../include/c++/12/bits/std_thread.h:231
#7  0x00007ffff7bf1253 in ?? () from /lib/x86_64-linux-gnu/libstdc++.so.6
#8  0x00007ffff7879ac3 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442
#9  0x00007ffff790b850 in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

Environment:
Operating System: Ubuntu 22.04
Provider: reproducer is using ofi_rxm but it may be irrelevant to a issue
Libfabric Version: 2.1.0
Clang:
clang version 18.1.8 Target: x86_64-unknown-linux-gnu Thread model: posix
On clang version 20.1.3 issue also persist.