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From: "bangerth at dealii dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/17112] default operator= for struct with packed bitfield is wrong
Date: Fri, 20 Aug 2004 12:50:00 -0000	[thread overview]
Message-ID: <20040820125040.19910.qmail@sourceware.org> (raw)
In-Reply-To: <20040819232250.17112.gene@digilicious.com>


------- Additional Comments From bangerth at dealii dot org  2004-08-20 12:50 -------
To see what really happens, here's a way to get a dump of the 
contents of the entire field: 
------------------ 
#include <iostream> 
                                                                                
                                                               
using namespace std; 
  
struct myint24 { 
  int int24:24  __attribute__ ((packed));  
}; 
  
myint24 x[3] = { 
  0x010203, 
  0x040506, 
  0x070809 
}; 
  
myint24 y[3];            // starts out as zeros 
  
int main(int ac, char* av[]) 
{ 
  y[1] = x[1]; 
  for ( int i=0; i<sizeof(y); ++i ) 
    cout << (int)*((char*)y + i) << endl; 
} 
-------------------------- 
 
This, for me, prints 
g/x> ./a.out  
0 
0 
0 
6 
5 
4 
9 
0 
0 
 
W. 

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17112


  parent reply	other threads:[~2004-08-20 12:50 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-08-19 23:22 [Bug c++/17112] New: " gene at digilicious dot com
2004-08-20 12:45 ` [Bug c++/17112] " bangerth at dealii dot org
2004-08-20 12:50 ` bangerth at dealii dot org [this message]
2004-08-20 20:23 ` gene at digilicious dot com
2004-09-23  2:48 ` [Bug middle-end/17112] Copying of packed bitfields " giovannibajo at libero dot it
2004-09-23  3:36 ` giovannibajo at libero dot it
2004-09-23 13:03 ` roger at eyesopen dot com
2004-09-23 13:16 ` giovannibajo at libero dot it
2004-09-23 13:29 ` roger at eyesopen dot com
2004-09-23 14:50 ` giovannibajo at libero dot it
2004-09-24  3:03 ` giovannibajo at libero dot it
2004-09-25  9:45 ` giovannibajo at libero dot it
2004-09-26 14:58 ` cvs-commit at gcc dot gnu dot org
2004-09-26 15:16 ` pinskia at gcc dot gnu dot org
2004-09-27 10:06 ` schwab at suse dot de
2004-09-27 10:09 ` schwab at suse dot de
2004-09-27 12:55 ` pinskia at gcc dot gnu dot org
2004-09-27 13:20 ` pinskia at gcc dot gnu dot org
2004-09-27 14:07 ` schwab at suse dot de

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