[Bug c/14141] New: static functions incorrectly generate multiple function descriptors

[Bug c/14141] New: static functions incorrectly generate multiple function descriptors

[jejb at steeleye dot com]

the 64 bit compiler is only used to generate kernels for linux (the particular
kernel I debugged this on is 2.6.3-rc1-pa2) so I don't have a user level
compileable example.

The problem arises because a particular piece of code in mm/shmap.c has a
function pointer comparison:

if (inode->i_op->truncate == shmem_truncate) 

Which is always evaluating false.  (shmem_truncate is a static function in shmem.c)

When I check, the Elf64_Fptr for each is different, but the address of the
function is the same.  hppa64 is supposed to have the OPD rule where there's
only one function descriptor per function, so we can evaluate this comparison by
comparing the addresses of the function descriptors.

The value of the function descriptor is assigned like this later in the same file:

static struct inode_operations shmem_symlink_inode_operations = {
        .truncate       = shmem_truncate,
        .readlink       = shmem_readlink,
        .follow_link    = shmem_follow_link,
};


As a test, if the function shmem_truncate is made unstatic, the comparison does
work successfully.

-- 
           Summary: static functions incorrectly generate multiple function
                    descriptors
           Product: gcc
           Version: 3.3.3
            Status: UNCONFIRMED
          Severity: critical
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: jejb at steeleye dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: hppa-linux
  GCC host triplet: hppa-linux
GCC target triplet: hppa64-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[jejb at steeleye dot com]

------- Additional Comments From jejb at steeleye dot com  2004-02-13 15:14 -------
Created an attachment (id=5748)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=5748&action=view)
The full shmem.c file from kernel 2.6.3-rc1-pa2


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-13 15:30 -------
This is a dup of bug 11197, the problem is partly an ABI problem and partly GCC not expanding the 
funtion comparision.

*** This bug has been marked as a duplicate of 11197 ***

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-02-13 15:52 -------
Reopening for now.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|critical                    |normal
             Status|RESOLVED                    |UNCONFIRMED
         Resolution|DUPLICATE                   |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[gmsoft at tuxicoman dot be]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |gmsoft at tuxicoman dot be


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[soete dot joel at tiscali dot be]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |soete dot joel at tiscali
                   |                            |dot be


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[danglin at gcc dot gnu dot org]

------- Additional Comments From danglin at gcc dot gnu dot org  2004-03-14 01:25 -------
Created an attachment (id=5912)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=5912&action=view)
Small test program that generates plabel field selectors for function foo in
different sections


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141

[Bug c/14141] static functions incorrectly generate multiple function descriptors

[danglin at gcc dot gnu dot org]

------- Additional Comments From danglin at gcc dot gnu dot org  2004-03-14 01:34 -------
I can duplicate the problem with the test program attached in fptr.tgz
using GNU ld on hppa64-hp-hpux11.11.  However, the problem doesn't occur
with the HP linker.  Given that hppa64 elf ports support named data sections,
we can't fix this in GCC.  This is a GNU ld bug.  Thus, I am marking
this PR as invalid.



-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |dave at hiauly1 dot hia dot
                   |                            |nrc dot ca
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |INVALID


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14141