c - xlC 警告 'Initialization between types "struct {...} *"and "int“不允许。”

Question

下面的程序om.c通过xlC编译成功，除了关于1506-196的警告!!!

谁能解释一下这样的警告信息!？

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
    char ch_sh[]="This is a program!!";
    char k1[1200];
    char *ls_sh=NULL;
    size_t len=0;
    FILE *om = open_memstream(&ls_sh, &len);
    fprintf(om, "   %32s", ch_sh);
    if ( argv[1] != NULL )
    {
        fprintf(om, "%26s", argv[1]);
        fclose(om);
        sprintf(k1, "echo %s", ls_sh);
        system(k1);
        printf("\ndone message in program\n");
    }
    else
    {
        printf("Error: Empty input\n");
        return 1;
    }
    free(ls_sh);
}

编译器日志:

 1. root@psph:/tmp# 
        root@psph:/tmp# 
        root@psph:/tmp# 
        root@psph:/tmp# xlC -o om om.c
        "om.c", line 11.14: 1506-196 (W) Initialization between types "struct {...}*" and "int" is not allowed.
        root@psph:/tmp# 
        root@psph:/tmp# xlC -qsrcmsg -o om om.c
               11 |     FILE *om = open_memstream(&ls_sh, &len);
                    .............a..............................
        a - 1506-196 (W) Initialization between types "struct {...}*" and "int" is not allowed.

        root@psph:/tmp# ./om data1    
        This is a program!! data1
        done message in program
        root@psph:/tmp# 
        root@psph:/tmp# xlC -qversion
        IBM XL C/C++ for AIX, V11.1 (5724-X13)
        Version: 11.01.0000.0000
        Driver Version: 11.01(C/C++) Level: 100304
        C Front End Version: 11.00(C/C++) Level: 100301
        C++ Front End Version: 11.01(C/C++) Level: 100304
        High-Level Optimizer Version: 11.01(C/C++) and 13.01(Fortran) Level: 100301
        Low-Level Optimizer Version: 11.01(C/C++) and 13.01(Fortran) Level: 100304
        root@psph:/tmp# 
        root@psph:/tmp# 
        root@psph:/tmp#

就这些!

Answer 1

警告说您正在影响指向指针的 int 值，这通常是由间接级别错误引起的。并且 open_memstream 不是标准 C 而是 POSIX。

这里，很可能对于xlC，open_memstream没有在stdio.h中声明。然后编译器假定它应该是一个返回 int 的函数，因此发出警告。您应该询问 man (man open_memstream) 以了解它在哪个包含文件中声明并将其包含在您的源代码中。