[Bug c++/58198] New: duplicate codes generated for variant function and base function

[Bug c++/58198] New: duplicate codes generated for variant function and base function

[chihin.ko at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58198

            Bug ID: 58198
           Summary: duplicate codes generated for variant function and
                    base function
           Product: gcc
           Version: 4.1.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: chihin.ko at oracle dot com

Created attachment 30675
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30675&action=edit
test case

This problem was fixed after g++ 4.4, I file this bug is only for book keeping.

test case was attached.

pirandello 1017> nm a.out | grep mybase
0000000000400528 T _ZN6mybase10mybasefuncEv
000000000040054e T _ZN6mybaseC1Ev  <=== base function
000000000040053a T _ZN6mybaseC2Ev  <=== variant function

base function (_ZN6mybaseC1Ev) and variant function (_ZN6mybaseC2Ev) should
have same addresses, but they're not.

Use gdb to debug a.out, shows bpt stop in variant function instead of base
function:


(gdb) b mybase::mybase
Breakpoint 1 at 0x400542: file base.cc, line 21. (2 locations)
(gdb) run
Starting program:
/net/benjamin2.us.oracle.com/export/ws/jeanko/dinstall/maxirun/intel-Linux/pirandello-chko/results/Customlist_list.master.maxi/gplus_base.dbx,gcc/a.out 

Breakpoint 1, mybase (this=0x7fff1343ed50) at base.cc:21
21        mybaseint = 5555; 
(gdb) disassemb $pc
Dump of assembler code for function mybase:
0x000000000040053a <mybase+0>:  push   %rbp
0x000000000040053b <mybase+1>:  mov    %rsp,%rbp
0x000000000040053e <mybase+4>:  mov    %rdi,-0x8(%rbp)
0x0000000000400542 <mybase+8>:  mov    -0x8(%rbp),%rax
0x0000000000400546 <mybase+12>: movl   $0x15b3,(%rax)
0x000000000040054c <mybase+18>: leaveq 
0x000000000040054d <mybase+19>: retq   
End of assembler dump.
(gdb) 

# disassemble base function address shows both functions has exact same codes
(gdb) disassemb 0x40054e
Dump of assembler code for function mybase:
0x000000000040054e <mybase+0>:  push   %rbp
0x000000000040054f <mybase+1>:  mov    %rsp,%rbp
0x0000000000400552 <mybase+4>:  mov    %rdi,-0x8(%rbp)
0x0000000000400556 <mybase+8>:  mov    -0x8(%rbp),%rax
0x000000000040055a <mybase+12>: movl   $0x15b3,(%rax)
0x0000000000400560 <mybase+18>: leaveq 
0x0000000000400561 <mybase+19>: retq   
End of assembler dump.
(gdb)

[Bug c++/58198] duplicate codes generated for variant function and base function

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58198

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
                 CC|                            |jakub at gcc dot gnu.org
         Resolution|---                         |FIXED

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
For book keeping of what?  GCC before 4.7.0 are no longer supported.

[Bug c++/58198] duplicate codes generated for variant function and base function

[chihin.ko at oracle dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58198

--- Comment #2 from chihin ko <chihin.ko at oracle dot com> ---
(In reply to Jakub Jelinek from comment #1)
> For book keeping of what?  GCC before 4.7.0 are no longer supported.

oracle solstudtio debugger dbx support gnu compiler v4.1 v4.5.2...etc, 
this is to show why dbx has problem with variant function.