[Bug c++/53762] pointer-casts don't always check null-pointers

2012-06-24 Thread pinskia at gcc dot gnu.org 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53762

Andrew Pinski  changed:

   What|Removed |Added

 Status|UNCONFIRMED |RESOLVED
 Resolution||INVALID

--- Comment #3 from Andrew Pinski  2012-06-24 
18:09:39 UTC ---
Invalid as mentioned as:
pa = &static_cast(*pb);
  ^^^
Deferences a null pointer at the caret.

[Bug c++/53762] pointer-casts don't always check null-pointers

2012-06-24 Thread redi at gcc dot gnu.org 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53762

--- Comment #2 from Jonathan Wakely  2012-06-24 
16:30:54 UTC ---
These are allowed:

  pa = static_cast(pb);
  pb = static_cast(pa);

All the other casts are not because they involve dereferencing a null pointer
which is not allowed by [expr.unary.op]/1

Also, GCC  4.2 is not supported or maintained so there's no point reporting
bugs against it, you should check a newer release before reporting bugs.

[Bug c++/53762] pointer-casts don't always check null-pointers

2012-06-24 Thread redi at gcc dot gnu.org 
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53762

Jonathan Wakely  changed:

   What|Removed |Added

   Severity|major   |normal

--- Comment #1 from Jonathan Wakely  2012-06-24 
16:26:17 UTC ---
Your program dereferences null pointers, that's undefined behaviour.