[Bug c++/33407] C++ operator new and new expression do not change dynamic type

[rguenth at gcc dot gnu dot org]

------- Comment #2 from rguenth at gcc dot gnu dot org  2007-09-12 10:13 -------
main should call init(), but it doesn't make a difference for the IL.  The
bug is wrong-IL for me only at the moment, but nothing prevents the two stores
from being reordered.

Here's one that abort()s at runtime on i686 with -O2 for me:  (same trick
as in PR29286, trick LIM into reordering the stores :))

extern "C" void * malloc(__SIZE_TYPE__);
extern "C" void abort(void);

void *p;
void __attribute__((noinline)) init(void)
{
  p = malloc(4);
}

inline void *operator new(__SIZE_TYPE__)
{
  return p;
}

inline void operator delete (void*) {}

int * __attribute__((noinline)) doit(int n)
{
  float *q;
  int *r;

  for (int i=0; i<n; ++i)
  {
    q = new float;
    *q = 1.0;
    delete q;
    r = new int;
    *r = 1;
  }

  return r;
}

int main()
{
  init();
  if (*doit(1) != 1)
    abort();
  return 0;
}


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33407