Very strange question

409616177

#include <iostream>
using namespace std;
int k = 1;
int main ()
{
int i = 4;
int fun (int);
Ranch
fun (i);
cout << "(1)" << i << ',' << k << endl;
return 0;
}

void fun (int m)
{
m + = k;
k + = m;
{
char k = 'B';
cout << "(2)" << char (k-'A ') << endl;
}
cout << "(3)" << m << ',' << k << endl;
}


This program compiles,
Why does it appear when running:
-------------------- Configuration: Cpp1-Win32 Debug --------------------
Linking ...
Cpp1.obj: error LNK2001: unresolved external symbol "int __cdecl fun (int)" (? Fun @@ YAHH @ Z)
Debug / Cpp1.exe: fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

Cpp1.exe-1 error (s), 0 warning (s)


what happened?

40668477

May be multiple debug windows opened.

409616177

Ah? No ...

wanxiaohai

It may be that the fun function is wrong, change int fun (int); to void fun (int) and try

wanxiaohai

I made the above modification on my machine and it works fine!

woharay

VC
C ++-> CodeGeneration changed Calling Converation to __cdecl during compilation

zyqp2000

#include <iostream>
using namespace std;
void fun (int m);
int k = 1;
void main ()
{
int i = 4;


fun (i);
cout << "(1)" << i << ',' << k << endl;

}

void fun (int m)
{
m + = k; // m = 5
k + = m; // k = 6
{
char (k = 'B');
cout << "(2)" << char (k-'A ') << endl;
}
cout << "(3)" << m << ',' << k << endl;
}

bebe0314

void fun (int m)

zhilong821

This is obviously because the linked interface cannot be found, the claim is inconsistent with the definition

qinqingshu

No problem on my machine.