如何在gdb中打印＜incomplete type＞变量 gdb

link

vi main1.cpp

#include <iostream>
#include <fstream>
#include <stdio.h>

using namespace std;
int main()
{
    ifstream inFile("test.txt", ios::in);


    //printf("%p",inFile);
    cout<<"inFile="<< !inFile<<endl;
    if (inFile)
        inFile.close();
    else
        cout << "test.txt doesn't exist" << endl;
    ofstream oFile("test1.txt", ios::out);
    if (!oFile)
        cout << "error 1";
    else
        oFile.close();
    fstream oFile2("./test2.txt", ios::out | ios::in);
    if (!oFile2)
        cout << "error 2";
    else
        oFile.close();
    return 0;
}

g++ -g main1.cpp -o main
gdb main
b 8
r 
n
p inFile 
print (void *)inFile

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Reading symbols from main...done.
(gdb) b 8
Breakpoint 1 at 0xef5: file main1.cpp, line 8.
(gdb) r 
Starting program: /home/ledi/cc/4/main 

Breakpoint 1, main () at main1.cpp:8
8	    ifstream inFile("test.txt", ios::in);
(gdb) n
13	    if (inFile)
(gdb) p inFile 
$1 = <incomplete type>
(gdb) print (void *)inFile
$2 = (void *) 0x7ffff7dc9410 <vtable for std::basic_ifstream<char, std::char_traits<char> >+24>