Invalid instruction in test_stack on E2K-v5 in protected mode about libatomic_ops

[ivmai]

Stacktrace (if compiled with -O3): // obtained by ulimit -c unlimited; while ./tests/test_stack; do :; done; gdb tests/test_stack core

#0  0x0000000050179ef8 in AO_stack_push_explicit_aux_release ()
#1  0x000000005017aaa0 in AO_stack_push_release ()
#2  0x00000000501772a0 in run_one_test ()
#3  0x0000000050203530 in start_thread () from /lib128/libpthread.so.0

gdb reports: Program terminated with signal SIGILL, Illegal instruction.

[ivmai]

gdb show exact line of SIGILL, if compiled with -O0 -g:

libatomic_ops/src/atomic_ops_stack.c

Line 158 in 7279f81

if (AO_EXPECT_FALSE(entry1 == x_bits || entry2 == x_bits))

#0  0x00000000501ab038 in AO_stack_push_explicit_aux_release (list=0x501b0180 <the_list>, x=0x50a16e80,
    a=0x501b0190 <the_list+16>) at atomic_ops_stack.c:158
158             if (AO_EXPECT_FALSE(entry1 == x_bits || entry2 == x_bits))

[ivmai]

How to reproduce ("quick how-to"):
git clone https://github.com/ivmai/libatomic_ops.git && cd libatomic_ops && git checkout 7279f8153 && gcc -m128 -O0 -g -I src -o test_stack tests/test_stack.c src/*.c -lpthread && ulimit -c unlimited && while ./test_stack; do :; done && gdb test_stack core

[ivmai]

As of commit cc9bc49, the issue is still reproduced.