分析其中 data race 问题，并预估输出结果。

adding.c

#include <adding.h>

void *adding(void *input) {
  struct Data *data = (struct Data *)input;
  for (int i = 0; i < 1000; i++) {
    data->acnt++;
    data->cnt++;
  }
  pthread_exit(NULL);
}

adding.h

#include <pthread.h>
#include <stdatomic.h>

struct Data {
  _Atomic int acnt;
  int cnt;
};

void *adding(void *input);

main.c

#undef NDEBUG
#include <assert.h>
#include <stdio.h>

#include <adding.h>

int main() {
  struct Data data;
  pthread_t tid[10];
  for (int i = 0; i < 10; i++) {
    pthread_create(&tid[i], NULL, adding, (void *)&data);
  }
  for (int i = 0; i < 10; i++) {
    pthread_join(tid[i], NULL);
  }

  printf("the value of acnt is %d\n", data.acnt);
  printf("the value of cnt is  %d\n", data.cnt);
  assert(data.acnt == 10000);
  assert(data.cnt == 10000);
  return 0;
}

Makefile

TARGET     = main.test

CFLAGS    += -std=c11 -I. -Os -pthread
LDFLAGS   +=
CPPFLAGS  += -Wall

all: main.o adding.o
	$(CC) -o $(TARGET) $? $(LDFLAGS) $(LDLIBS)

test:
	./$(TARGET)

clean:
	$(RM) *.o *.test