[Bug c++/25386] New: packed structs

["nathan at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

g++.dg/ext/packed3.C fails on default packed targets.

I don't think this is the case. The questionable code (from the test
case) really is

struct Unpacked { int i; };
struct  __attribute__ ((packed)) Packed
{
  char c;
  int i;
  Unpacked u;
};

and the test expects that you cannot bind Packed::u to Unpacked& (error
expected), but that you can bind Packed::u::i to int& (not even a
warning expected). No warning is expected on the definition of Packed's
u member.
Not exactly. My problems are

(a) the above mentioned inconsistency in allowing binding to the whole
structure but not to its members, and

(b) on a default-packed target (or with -fpack-struct) getting reverse
behavior in allowing binding to Packed::u but not allowing binding to
Packed::u::i.

>% ah, I think that warning should only be given on non-default-packed
>> arches. Is this your problem Jan?


I think the warning should be given only if the base class does not
itself have the minimum alignment for the artchitecture.  (So that you
would get the warning on a system that was packed by default if you used
a base class which was explicitly aligned on a wider boundary.)


-- 
           Summary: packed structs
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: nathan at gcc dot gnu dot org
GCC target triplet: *-*-netware*


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=25386