NO_INT_TRAPS.cpp

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// checking if integer math traps
 
 
#include "nodbg.h"
 
 
#if defined (_MSC_VER)
#  define TRY             __try
#  define EXCEPT(expr)    __except (expr)
#else   // not MSVC
#  define TRY               if (1)
#  define EXCEPT(ignore)    else if (0)
#endif   // _MSC_VER
 
 
int get_int (int);
 
 
volatile int int_zero;
volatile int int_one;
 
 
int main (int argc, char*[])
{
    nodbg ();
 
    // test expects to be called with no command line arguments
    // i.e., (argc < 2) is expected to hold
 
    // argc used to try to foil optimizers
    int_zero = get_int (argc);
    int_one  = get_int (argc);
 
    int result [2];
 
    TRY {
        // use both division and modulo to try to foil optimizers
        result [0] = int_one / int_zero;
        result [1] = int_one % int_zero;
    }
    EXCEPT (1) {
        return 1;
    }
 
    // NEGATIVE test: successful exit status indicates a failure
    return argc < 2 ? result [0] : result [1];
}
 
// use volatile to try to foil optimizers
volatile int int_value;
 
// use recursion to try to foil optimizers
int get_int (int arg)
{
    if (1 < arg)
        return get_int (arg - 1) + get_int (arg - 2);
 
    const int value = int_value;
 
    ++int_value;
 
    return value;
}