will this be compiler(M$ cl) bug or Memory leakage?
-
#include
#define unsafe(i) \
( (i) >= 0 ? (i) : -(i) )inline
int safe(int i)
{
return i >= 0 ? i : -i;
}
int f() {cout << "Called f()!" << endl; return 0;};
void userCode(int x)
{
int ans;
ans = unsafe(x++); // Error! x is incremented twice
cout << "[1] "<< x << endl;
// ans = (f()) >= 0 ? (f()) : -(f());
ans = unsafe(f()); // Danger! f() is called twice
cout << "[2] "<< x << endl;ans = safe(x++); // Correct! x is incremented once
cout << "[3] "<< x << endl;
ans = safe(f()); // Correct! f() is called once
cout << "[4] "<< x << endl;
}void main(void)
{
userCode(100);
}I was doing a test code for inline functions comparison to macros. The original code was shown as above, things seemed normal as the result showed two times of
f()calls. The result looked like:[1] 102
Called f();
Called f();
[2] 102
[3] 103
Called f();
[4] 103However, after I tried to call
ans = (f()) >= 0 ? (f()) : -(f());instead ofans = unsafe(f());, I got a result of callingf()FOUR times instead of TWO times as supposed. In this tread, I failed to attach a image of the result, which looked like:[1] 102
Called f();
Called f();
Called f();
Called f();
[2] 102
[3] 103
Called f();
[4] 103I ran the program twice both of times I got calling
f()FOUR times, nevertheless, I could repeat the result after I re-compiled the program again with the original code. Could this be a compiler bug? DJ -
#include
#define unsafe(i) \
( (i) >= 0 ? (i) : -(i) )inline
int safe(int i)
{
return i >= 0 ? i : -i;
}
int f() {cout << "Called f()!" << endl; return 0;};
void userCode(int x)
{
int ans;
ans = unsafe(x++); // Error! x is incremented twice
cout << "[1] "<< x << endl;
// ans = (f()) >= 0 ? (f()) : -(f());
ans = unsafe(f()); // Danger! f() is called twice
cout << "[2] "<< x << endl;ans = safe(x++); // Correct! x is incremented once
cout << "[3] "<< x << endl;
ans = safe(f()); // Correct! f() is called once
cout << "[4] "<< x << endl;
}void main(void)
{
userCode(100);
}I was doing a test code for inline functions comparison to macros. The original code was shown as above, things seemed normal as the result showed two times of
f()calls. The result looked like:[1] 102
Called f();
Called f();
[2] 102
[3] 103
Called f();
[4] 103However, after I tried to call
ans = (f()) >= 0 ? (f()) : -(f());instead ofans = unsafe(f());, I got a result of callingf()FOUR times instead of TWO times as supposed. In this tread, I failed to attach a image of the result, which looked like:[1] 102
Called f();
Called f();
Called f();
Called f();
[2] 102
[3] 103
Called f();
[4] 103I ran the program twice both of times I got calling
f()FOUR times, nevertheless, I could repeat the result after I re-compiled the program again with the original code. Could this be a compiler bug? DJWhat compiler are you using? I can't repro the problem on VC 6 SP 5. --Mike-- Personal stuff:: Ericahist | Homepage Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ ---- Kosh reminded me of some of the prima-donna programmers I've worked with. Knew everything but when you asked them a question; never gave you a straight answer. -- Michael P. Butler in the Lounge
-
What compiler are you using? I can't repro the problem on VC 6 SP 5. --Mike-- Personal stuff:: Ericahist | Homepage Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ ---- Kosh reminded me of some of the prima-donna programmers I've worked with. Knew everything but when you asked them a question; never gave you a straight answer. -- Michael P. Butler in the Lounge
Microsoft Compiler Ver 12.00.8168 from VC++ 6. I could not reproduce the problem either. So I guess the chance would be high that I accidently uncommented both
ans = (f()) >= 0 ? (f()) : -(f());andans = unsafe(f());. So far, I could not think out other reasons. DJ