[Bug c++/19508] [4.0 regression] dwarf2, ICE on __attribute__(aligned) in class template

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2005-01-20 12:09 -------
The problem here is that tsubst does not know about attributes, and we knew 
this already. So it won't look into DECL_ORIGINAL_TYPE because it assumes it is 
always NULL for template parameters. You may want to notice that the attribute 
is in fact ignored:

--------------------------------------------------------
template <typename T>  
struct BVector  
{  
  typedef T value_type __attribute__ ((aligned(8)));  
  value_type v;
};  
BVector<int> m;  

int main()
{
  printf("%d\n", __alignof__(m.v));
}
--------------------------------------------------------

This prints "4" on i686-pc-linux-gnu (if you compile it without -g to avoid the 
ICE).

I tried tsubsting within the ORIGINAL_TYPE of a TYPE_DECL too, and it works in 
avoiding the ICE, but for nothing else. Also, the long-term solution is to not 
apply attributes to template types, store the attribute list aside and apply it 
after substitution. So, after all, this would not be a step forward not even in 
that direction.

Thus, it is better to simply not apply the attribute to template types at all.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |giovannibajo at libero dot
                   |dot org                     |it
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2005-01-20 04:36:26         |2005-01-20 12:09:35
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19508