https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71916
--- Comment #10 from Martin Liška <marxin at gcc dot gnu.org> ---
Couple of observations:
1) the second test-case triggers undefined behavior in:
g[i] = 9;
/home/marxin/Programming/testcases/pr71916-2-original.c:20:8: runtime error:
index 4 out of bounds for type 'char [4]'
/home/marxin/Programming/testcases/pr71916-2-original.c:20:12: runtime error:
store to address 0xffe64530 with insufficient space for an object of type
'char'
2) cunrolli pass determines that following loop iterates 5 times (because of
g[4] array):
pr71916-2-original.c:11:6: note: loop with 5 iterations completely unrolled
Latch of last iteration was marked by __builtin_unreachable ().
3) --dbg-cnt="registered_jump_thread:4" is the first jump threading which
triggers the ICE. It adds jump to the BB with __builtin_unreachable.
