c - 从不兼容的指针警告初始化

Question

我有一个警告，但我不明白为什么:

void stampaCon(){
pthread_mutex_lock(&mutexCon);

  printf("lista dei connesi: \n");
  int i;
    for(i=0; i<=MAX_CONNECTIONS*8; i++){
        if(arrayCon[i]!=NULL){
            TipoListaReg *s = NULL;

            s = arrayCon[i]; //gives me a warning

            printf("utente %s\n", arrayCon[i]->utente);
            while(s->next!=NULL){
                printf("utente %s\n", s->next->utente);
                s=s->next;
            }
        }
    }

    pthread_mutex_unlock(&mutexCon);

TipoListaReg 结构是:

typedef struct NodoListaReg { 
  char utente[MAX_NAME_LENGTH+1];
  int connesso; 
  ListaPendente *msgs;
  struct NodoListaReg *next;
} TipoListaReg;

arrayReg 是一个全局变量，定义为:

TipoListaReg *arrayReg[512];

这是一个 ListaPendente 结构体:

typedef struct pendenti{ 

  char msg[MAX_MSG_SIZE];
  char mittente[MAX_NAME_LENGTH+1];
  int type;
  struct pendenti *next;
}ListaPendente;

警告是:

warning: assignment from incompatible pointer type [-Wincompatible-pointer-types]

Answer 1

您的问题中确实没有足够的信息，但是编译正常，没有警告:

typedef struct ListaPendente  // made up definition by me as you didn't provide
{                             // the definition of ListaPendente 
  int dummy;
} ListaPendente ;

typedef struct NodoListaReg {
  char utente[100];           // MAX_NAME_LENGTH replaced by 100 as it is not relevant
  int connesso;
  ListaPendente *msgs;
  struct NodoListaReg *next;
} TipoListaReg;

TipoListaReg *arrayReg[512];

int main()
{
  int i = 0;
  TipoListaReg *s = arrayReg[i];    // no warning here
}

但是代码不会做任何有用的事情