Question

/* Includes */
#include <unistd.h>     /* Symbolic Constants */
#include <sys/types.h>  /* Primitive System Data Types */ 
#include <errno.h>      /* Errors */
#include <stdio.h>      /* Input/Output */
#include <stdlib.h>     /* General Utilities */
#include <pthread.h>    /* POSIX Threads */
#include <string.h>     /* String handling */

/* prototype for thread routine */
void print_message_function ( void *ptr );

/* struct to hold data to be passed to a thread
   this shows how multiple data items can be passed to a thread */
typedef struct str_thdata
{
    int thread_no;
    char message[100];
} thdata;

int main()
{
    pthread_t thread1, thread2;  /* thread variables */
    thdata data1, data2;         /* structs to be passed to threads */

    /* initialize data to pass to thread 1 */
    data1.thread_no = 1;
    strcpy(data1.message, "Hello!");

    /* initialize data to pass to thread 2 */
    data2.thread_no = 2;
    strcpy(data2.message, "Hi!");

    /* create threads 1 and 2 */    
    pthread_create (&thread1, NULL, (void *) &print_message_function, (void *) &data1);
    pthread_create (&thread2, NULL, (void *) &print_message_function, (void *) &data2);

    /* Main block now waits for both threads to terminate, before it exits
       If main block exits, both threads exit, even if the threads have not
       finished their work */ 
    pthread_join(thread1, NULL);
    pthread_join(thread2, NULL);

    /* exit */  
    exit(0);
} /* main() */

/**
 * print_message_function is used as the start routine for the threads used
 * it accepts a void pointer 
**/
void print_message_function ( void *ptr )
{
    thdata *data;            
    data = (thdata *) ptr;  /* type cast to a pointer to thdata */

    /* do the work */
    printf("Thread %d says %s \n", data->thread_no, data->message);

    pthread_exit(0); /* exit */
} /* print_message_function ( void *ptr ) */

我遇到的错误是 thread-ex.c：24：5：错误：未知类型名称＆＃39; pthread_t＆＃39; pthread_t thread1，thread2; / *线程变量* / ^ thread-ex.c：36：5：警告：隐式声明函数＆＃39; pthread_create＆＃39; [-Wimplicit函数声明] pthread_create（＆amp; thread1，NULL，（void *）＆amp; print_message_function，（void ）＆amp; data1）; ^ thread-ex.c：42：5：警告：隐式声明函数＆＃39; pthread_join＆＃39; [-Wimplicit函数声明] pthread_join（thread1，NULL）; ^ thread-ex.c：在函数＆＃39; print_message_function＆＃39;： thread-ex.c：61：5：警告：隐式声明函数＆＃39; pthread_exit＆＃39; [-Wimplicit函数声明] 了pthread_exit（0）; / 退出* /

Answer 1

pthreads不适用于基于newlib的RISC-V编译器。您将需要使用基于linux的RISC-V编译器（riscv64-unknown-linux-gnu-gcc）。您可以在相同的riscv-gcc repo（https://github.com/riscv/riscv-gnu-toolchain）中找到构建和安装基于linux的编译器的说明。

使用riscv64-unknown-elf-gcc编译的多线程程序的编译错误

1 个答案: