cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations pthread/pthread_testcancel.c -o pthread/pthread_testcancel -D_POSIX_C_SOURCE=202405L -lm -lpthread -lrt -lintl -liconv
pthread/pthread_testcancel.c:5:21: error: ‘pthread_testcancel’ undeclared here (not in a function); did you mean ‘pthread_detach’?
    5 | void (*foo)(void) = pthread_testcancel;
      |                     ^~~~~~~~~~~~~~~~~~
      |                     pthread_detach