问题
Can you give an example of stack overflow in C++? Other than the recursive case:
void foo() { foo(); }
回答1:
The typical case that does not involve infinite recursion is declaring an automatic variable on the stack that is too large. For example:
int foo()
{
int array[1000000];
}
回答2:
Please see Stack overflow - Wikipedia. I have linked directly to the examples section.
回答3:
void function()
{
function();
}
回答4:
Here's one that might happen in practice:
int factorial(int x) {
return x == 0 ? 1 : x * factorial(x-1);
}
This overflows the stack for negative x
. And, as Frank Krueger mentioned, also for too large x
(but then int
would overflow first).
回答5:
Keep trying to return main until the stack runs out?
int main(int argc, char **argv)
{
return main(argc, argv);
}
回答6:
As per edit :-)
void ping()
{
pong();
}
void pong()
{
ping();
}
Also, I believe you can get stack overflow if you try to allocate more space than maximum thread stack size ( 1MB by default in VS), so something like int a[100000];
should provide the exception.
回答7:
Compile-time example:
template <int N>
struct Factorial {
enum { value = N * Factorial<N - 1>::value };
};
// ...
{
int overflow = Factorial<10>::value;
}
回答8:
I can't believe we left off the greatest recursion example of all time, factorial!
#include <stdio.h>
double fact(double n) {
if (n <= 0) return 1;
else return n * fact(n - 1);
}
int main() {
printf("fact(5) = %g\n", fact(5));
printf("fact(10) = %g\n", fact(10));
printf("fact(100) = %g\n", fact(100));
printf("fact(1000) = %g\n", fact(1000));
printf("fact(1000000) = %g\n", fact(1000000));
}
On OS X 10.5.8 with GCC 4.0.1:
$ gcc f.c -o f && ./f
fact(5) = 120
fact(10) = 3.6288e+06
fact(100) = 9.33262e+157
fact(1000) = inf
Segmentation fault
Unfortunately, OS X reports a "Segmentation fault" instead of a "Stack overflow". Too bad.
回答9:
This example shows uncontrolled recursion. Eventually, the stack spaced allocated to this process will be completely overwritten by instances of bar and ret...
int foo( int bar )
{
int ret = foo( 42 );
return ret;
}
回答10:
If you want to generate an explicitly non-recursive program to result in a stack overflow by function calls:
#!/usr/bin/env python
import sys
print "void func" + sys.argv[1] + "() { }"
for i in xrange(int(sys.argv[1])-1, -1, -1):
print "void func" + str(i) + "() { func" + str(i+1) + "(); }"
print "int main() { func0(); return 0; }"
Sample output:
$ python recursion.py 5
void func5() { }
void func4() { func5(); }
void func3() { func4(); }
void func2() { func3(); }
void func1() { func2(); }
void func0() { func1(); }
int main() { func0(); return 0; }
Sample usage:
$ python recursion.py 250000 | g++ -x c++ - && ./a.out
At least on my system, the call stack seems to be 174602, so you'll need to set the argument to recursion.py
to be larger than that; and it takes a few minutes to compile and link the program.
回答11:
Infinite recursion:
void infiniteFunction() { infiniteFunction(); } int main() { infiniteFunction(); return 0; }
回答12:
You could also get a stack overflow if you try to put large objects on the stack (by-value).
来源:https://stackoverflow.com/questions/1657484/can-you-give-an-example-of-stack-overflow-in-c