from http://www-1.ibm.com/support/docview.wss?uid=swg21211974

TestRT: Run-Time Check Failure #2 - Stack around the variable 'xxx' was corrupted.
Technote (FAQ)

Problem
The following error message occurs when building on Test RealTIme environment with the cvisual7 TDP?

Run-Time Check Failure #2 - Stack around the variable 'xxx' was corrupted.

Cause
Stack pointer corruption is caused writing outside the allocated buffer in stack memeory.

Solution
This kind of error is detected by setting /RTC1 compiler option from menu Project -> Settings -> Configuration properties -> Build -> Compiler -> Compiler flags when using TDP cvisual7 in IBM® Rational® Test RealTime environment.. This enables stack frame run-time error checking. For example, the following code may cause the above error messge.

#include <stdio.h>
#include <string.h>

#define BUFF_LEN 11 // 12 may fix the Run-Time Check Failure #2
int rtc_option_test(char * pStr);

int main()
{
char * myStr = "hello world";
rtc_option_test(myStr);
return 0;
}

int rtc_option_test(char * pStr)
{
char buff[BUFF_LEN];
strcpy(buff, pStr); //cause Run-Time Check Failure #2 - Stack around
//the variable 'buff' was corrupted.
return 0;
}