[Valgrind-users] The bug that got away...

[Peter T. <pt...@li...>]

 Hi all

 Try to find the errors in this C/C++ snippet using valgrind:

 #include <stdio.h>
 /* Save as code.c */
 int main(void)
 {
  int i=-1,a[2],b[2],c[2];
  a[0] = 1; a[1] = 2;
  b[0] = 3; b[1] = 4;
  c[0] = 5; c[1] = 6;
  printf("%i %in",b[i],a[i]);
  return 0;
 }

 Compile using "gcc -o bla code.c -Wall" and check the code using 
 "valgrind ./bla".
 Valgrind finds nothing even though I index a[-1] and b[-1] - not 
 good...

 Insure++ would for sure find the negative index, but GCC nor Valgrind 
 will get it...

 Are there supplementary tools I should check? Or can I in some way 
 supplement my compile process so that valgrind could alert me?

 Obviously I could augment the code so the the bad negative value of "i" 
 could be found from runtime specific parameters, i.e. static code 
 checking is not relevant for me.



 Best

 /pto

-- 
 Peter Toft, PhD
 http://petertoft.dk