cc -O2 -pipe  -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations signal/sigwaitinfo.c -o signal/sigwaitinfo -D_POSIX_C_SOURCE=202405L  -lm -lpthread 
signal/sigwaitinfo.c:5:61: error: use of undeclared identifier 'sigwaitinfo'
int (*foo)(const sigset_t *restrict, siginfo_t *restrict) = sigwaitinfo;
                                                            ^
1 error generated.