[Bug libstdc++/38477] [strict-aliasing] warning message contains compiler-generated symbols

[rguenth at gcc dot gnu dot org]

------- Comment #4 from rguenth at gcc dot gnu dot org  2008-12-12 11:24 -------
The access is
  ((const struct _Rb_tree_node *)
     &ctx.foo._M_t._M_impl._M_header.D.9518)->_M_value_field.pair_ptr

but _M_header is of type _Rb_tree_node_base (and is embedded in _M_impl).
 _Rb_tree_node_base does not have a _M_value_field member, so I do not see
that the memory that is accessed is really "there".  This "D.9518" thing
may somehow magically cover for it (but it's at offset zero of _M_header),
but certainly TBAA isn't aware that this is a legal access.

Of course I lack complete understanding of how the implementation details
of the rb tree are supposed to work.  So, if this is not a libstdc++
problem then it is a C++ FE problem.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38477