/opt/IBM/openxlC/17.1.1/bin/ibm-clang -pthread  -Wall -Wextra -Werror=implicit-function-declaration spawn/posix_spawn_file_actions_addchdir.c -o spawn/posix_spawn_file_actions_addchdir -D_GNU_SOURCE -D_BSD_SOURCE -D_ALL_SOURCE -D_DEFAULT_SOURCE -lm -lpthread -lrt -latomic
spawn/posix_spawn_file_actions_addchdir.c:40:16: error: call to undeclared function 'posix_spawn_file_actions_addchdir'; ISO C99 and later do not support implicit function declarations [-Werror,-Wimplicit-function-declaration]
        if ( (errno = posix_spawn_file_actions_addchdir(&actions, "spawn")) )
                      ^
spawn/posix_spawn_file_actions_addchdir.c:40:16: note: did you mean 'posix_spawn_file_actions_addclose'?
/usr/include/spawn.h:84:5: note: 'posix_spawn_file_actions_addclose' declared here
int posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *, int);
    ^
1 error generated.