https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112112
--- Comment #6 from κΉλμ <22s302h0659 at sonline20 dot sen.go.kr> --- ``` z3rodae0@z3rodae0:~$ ./sh.sh result for -O0 "signed" = 1 result for -O1 "signed" = 1 result for -O2 "signed" = 1 result for -O3 "signed" = 1 result for -O0 "unsigned" = 0 result for -O1 "unsigned" = 0 result for -O2 "unsigned" = 0 result for -O3 "unsigned" = 0 result for -O0 "" = 1 result for -O1 "" = 1 result for -O2 "" = 1 result for -O3 "" = 1 ``` That's correct. I ran your code and script in my environment, and it produced the same results