#tar xvfz valgrind-1.0.0.tar.gz
             #cd valgrind-1.0.0
             #./configure
             #make
             #make install

#include <stdlib.h>
int main()
{
        int *p, *a;
        p = malloc(10*sizeof(int));
        a = malloc(10*sizeof(int));
        a[3] = p[3];
        free(a);
        free(p);
        return 0;
}

/*  produce no errors */

#include <stdlib.h>
int main()
{
        float *p, *a;
        p = malloc(10*sizeof(float));
        a = malloc(10*sizeof(float));
        a[3] = p[3];
        free(a);
        free(p);
        return 0;
}

/* produces error */

==7436== I1  refs:      12,841
==7436== I1  misses:       238
==7436== L2i misses:       237
==7436== I1  miss rate:   1.85%
==7436== L2i miss rate:   1.84%
==7436==
==7436== D   refs:       5,914  (4,626 rd + 1,288 wr)
==7436== D1  misses:       357  (  324 rd +    33 wr)
==7436== L2d misses:       352  (  319 rd +    33 wr)
==7436== D1  miss rate:    6.0% (  7.0%   +   2.5%  )
==7436== L2d miss rate:    5.9% (  6.8%   +   2.5%  )
==7436==
==7436== L2 refs:          595  (  562 rd +    33 wr)
==7436== L2 misses:        589  (  556 rd +    33 wr)
==7436== L2 miss rate:     3.1% (  3.1%   +   2.5%  )

   L2i misses means the number of instruction misses that occur in L2
cache.
   L2d misses means the number of data misses that occur in L2 cache.
   Total number of data references = Number of reads + Number of writes.
   Miss rate means fraction of misses that are not found in the upper
level.