Illegal stack operations can lead to hard to detect crashes. This typically takes place when a program passes a pointer of the wrong type to a function. The example given below shows a case of a function expecting an integer pointer and the caller passes a pointer to a character.
http://www.eventhelix.com/realtimemantra/Basics/debugging_software_crashes.htm
| char pointer/int pointer mixup |
main()
{
char count;
// The routine expects a int pointer but a char pointer has been passed
// Older compilers and non ANSI C compilers do not catch this error
GetCount(&count);
// The called function was expecting an int (say 4 byte) variable. It was
// however passed a char pointer with one byte space. GetCount will still
// write four bytes, thus corrupting local variables or parameters on the
// stack
}
bool GetCount(int *pCount)
{
. . .
*pCount = returnValue;
return true;
}
|
