clang -O2  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations signal/SA_SIGINFO.c -o signal/SA_SIGINFO -D_POSIX_C_SOURCE=202405L  -lm  -lintl
signal/SA_SIGINFO.c:2:17: error: use of undeclared identifier 'SA_SIGINFO'
int const foo = SA_SIGINFO;
                ^
1 error generated.