[Bug c/28865] New: Structures with a flexible arrray member have wrong .size

[Bug c/28865] New: Structures with a flexible arrray member have wrong .size

[qrczak at knm dot org dot pl]

For example this C:
struct {int x; int y[];} obj = {1, {2, 3}};

produces this assembly:

.globl obj
        .data
        .align 4
        .type   obj, @object
        .size   obj, 4
obj:
        .long   1
        .long   2
        .long   3

.size should include the flexible array component.


-- 
           Summary: Structures with a flexible arrray member have wrong
                    .size
           Product: gcc
           Version: 4.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: qrczak at knm dot org dot pl
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28865

[Bug middle-end/28865] Structures with a flexible arrray member have wrong .size

[qrczak at knm dot org dot pl]

------- Comment #1 from qrczak at knm dot org dot pl  2006-08-27 22:15 -------
A question: when this is fixed, what should be C-level sizeof obj?

I hope it would include the flexible array component. This would allow to
detect in autoconf whether this bug is fixed, and would be consistent with
toplevel arrays whose sizes are derived from their initializer.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28865

[Bug middle-end/28865] Structures with a flexible arrray member have wrong .size

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2006-08-28 03:08 -------
Confirmed, not a regression.


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
  GCC build triplet|i686-pc-linux-gnu           |
   GCC host triplet|i686-pc-linux-gnu           |
 GCC target triplet|i686-pc-linux-gnu           |
      Known to fail|                            |3.0.4 4.0.0 4.1.0 4.2.0
                   |                            |3.3.3 3.2.3 3.4.0
   Last reconfirmed|0000-00-00 00:00:00         |2006-08-28 03:08:51
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28865

[Bug middle-end/28865] Structures with a flexible arrray member have wrong .size

[lauro dot venancio at gmail dot com]

------- Comment #3 from lauro dot venancio at gmail dot com  2007-12-03 23:42 -------
I think I'm facing a related problem. GCC is emitting unaligned array elements. 

struct ccstm {
        int32_t val;
        const char descr[];
};

static const struct ccstm canon_d30custom[] = {
  { 1, "Long exposure noise reduction" },
  { 2, "Shutter/AE lock buttons" },
  { 3, "Mirror lockup" }
};

produces this assembly for arm-linux-gnueabi:

.align 2
canon_d30custom:
.word 1
.ascii "Long exposure noise reduction\000"
.word 2
.ascii "Shutter/AE lock buttons\000"
.word 3
.ascii "Mirror lockup\000"

Note that the second and the third array element are unaligned.


-- 

lauro dot venancio at gmail dot com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |lauro dot venancio at gmail
                   |                            |dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28865