[Bug c++/14865] New: Instanciation problem of template class derived from virtual base class

[Bug c++/14865] New: Instanciation problem of template class derived from virtual base class

[Clement dot Menier at inrialpes dot fr]

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Here is the test example that causes the problem. I tried to reduce it to its
strict minimum:

test.cpp:

#include <string>

class A  {
  std::string mesg;
};

class B : public virtual A {};

template <class Type> class C : public B {};

int main() {
  C<int> j;
}

By compiling it with g++ 3.3.1 (Mandrake 9.2):
   g++ -O1 -o test test.cpp

Returns error:

/tmp/ccwnGZD1.o(.text+0x23): In function `main':
: undefined reference to `VTT for C<int>'
collect2: ld a retourné 1 code d'état d'exécution

  It seems that it has some problem instanciating the template class C<int>
automatically. Here are different tests that DO work (each test is independant):

   - replace "std::string mesg" by "int mesg"
   - manually instanciate template class by putting
        "template class C<int>;"
      just before the main declaration
   - Move the delaration of j outside of main (global definition)
   - Compile with no optimisation (-O0 for example)

To clarify things I tested this under:
   gcc 3.3.1 by Mandrake 9.2 : Failed
   gcc 3.3.2 by Fedora : Failed
   gcc 3.3.3 home compiled (with no options) : Failed

   gcc 3.2.2 by RedHat 9 : Work

I thus suspect that this problem appeared with gcc versions 3.3 . It may also be
that gcc 3.3 is more strict on the code but I have found no indication to suport
this.

Clement Menier.

-- 
           Summary: Instanciation problem of template class derived from
                    virtual base class
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: Clement dot Menier at inrialpes dot fr
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: i686-px-linux-gnu
GCC target triplet: i686-px-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3 Regression] Instanciation problem of template class derived from virtual base class

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-04-06 14:07 -------
Confirmed in 3.3.3 (but note this is fixed in 3.4.0 already but it is a regression from 3.2.3 so keeping 
open still).

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |wrong-code
      Known to fail|                            |3.3.3 3.3.1
      Known to work|                            |3.4.0 3.5.0 3.2.3
   Last reconfirmed|0000-00-00 00:00:00         |2004-04-06 14:08:00
               date|                            |
            Summary|Instanciation problem of    |[3.3 Regression]
                   |template class derived from |Instanciation problem of
                   |virtual base class          |template class derived from
                   |                            |virtual base class
   Target Milestone|---                         |3.3.4


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] No instantiation of VTT at -O1

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-04-15 14:24 -------
Here's a reduced example. It gives linker errors when compiled with -O
since gcc 3.3. Alas even 3.4 branch and mainline fail. :-(

====================================================
struct A
{
    virtual ~A() {}
};

struct B : public virtual A {};

template <typename> struct C : public B {};

int main()
{
    C<int> c;
    return 0;
}
====================================================


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |reichelt at gcc dot gnu dot
                   |                            |org
           Keywords|                            |monitored
      Known to fail|3.3.3 3.3.1                 |3.3 3.3.1 3.3.2 3.3.3 3.3.4
                   |                            |3.4.0 3.5.0
      Known to work|3.4.0 3.5.0 3.2.3           |3.2.3
            Summary|[3.3 Regression] No         |[3.3/3.4/3.5 Regression] No
                   |instantiation of VTT at -O1 |instantiation of VTT at -O1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-05-03 05:03 -------
Adding note that this fails at -O2 or above with -fno-unit-at-a-time.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[3.3/3.4/3.5 Regression] No |[3.3/3.4/3.5 Regression]
                   |instantiation of VTT at -O1 |[no-unit-at-a-time] No
                   |                            |instantiation of VTT at -O1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  BugsThisDependsOn|                            |15816


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[giovannibajo at libero dot it]

------- Additional Comments From giovannibajo at libero dot it  2004-06-06 03:37 -------
Retargeting to 3.4.1, being a regression on that release branch.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |gdr at gcc dot gnu dot org
   Target Milestone|3.3.4                       |3.4.1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[reichelt at gcc dot gnu dot org]

------- Additional Comments From reichelt at gcc dot gnu dot org  2004-06-15 09:23 -------
Fixed on mainline by Andrew's patches to cp-tree.h:

http://gcc.gnu.org/ml/gcc-cvs/2004-06/msg00050.html
http://gcc.gnu.org/ml/gcc-cvs/2004-06/msg00055.html

(the second patch fixes a typo in the first one).

Since the respective lines in cp-tree.h are the same on the
3.3 and 3.4 branch a backport seems to be easy.

Andrew, will you give it a try?


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |pinskia at gcc dot gnu dot
                   |                            |org
      Known to fail|3.3 3.3.1 3.3.2 3.3.3 3.3.4 |3.3 3.3.1 3.3.2 3.3.3 3.3.4
                   |3.4.0 3.5.0                 |3.4.0
      Known to work|3.2.3                       |3.2.3 3.5.0
            Summary|[3.3/3.4/3.5 Regression]    |[3.3/3.4 Regression] [no-
                   |[no-unit-at-a-time] No      |unit-at-a-time] No
                   |instantiation of VTT at -O1 |instantiation of VTT at -O1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-15 13:44 -------
No because the patch is wrong in the first place and causes another regression which is even worse 
than this one, it causes QT to fail at build at -O0.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-15 20:56 -------
This was just broken again on the mainline by my patch to revert the patch which fixes it but the 
orginal patch was broken in the first place.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[3.3/3.4 Regression] [no-   |[3.3/3.4/3.5 Regression]
                   |unit-at-a-time] No          |[no-unit-at-a-time] No
                   |instantiation of VTT at -O1 |instantiation of VTT at -O1


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-06-24 21:16 -------
Patch here: <http://gcc.gnu.org/ml/gcc-patches/2004-06/msg01979.html>.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |patch


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2004-06-25 21:37 -------
Jan, did this patch test out OK?

If not, would some else care to test the patch?  It is OK if it passes tests.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jh at suse dot cz


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[jh at suse dot cz]

------- Additional Comments From jh at suse dot cz  2004-06-25 21:55 -------
Subject: Re:  [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

> 
> ------- Additional Comments From mmitchel at gcc dot gnu dot org  2004-06-25 21:37 -------
> Jan, did this patch test out OK?
> 
> If not, would some else care to test the patch?  It is OK if it passes tests.

It passed for 3.4 and mainline, it didn't apply clearly to 3.3.  I will
update it for 3.3 and re-test and apply if passes after 30th.  (I can
access the net only once a day this week, so this caused the delay)

Honza
> 
> -- 
>            What    |Removed                     |Added
> ----------------------------------------------------------------------------
>                  CC|                            |jh at suse dot cz
> 
> 
> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865
> 
> ------- You are receiving this mail because: -------
> You are on the CC list for the bug, or are watching someone who is.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-06-25 21:59 -------
Subject: Bug 14865

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	gcc-3_4-branch
Changes by:	hubicka@gcc.gnu.org	2004-06-25 21:59:08

Modified files:
	gcc/cp         : ChangeLog decl2.c 

Log message:
	PR C++/14865
	* decl2.c (maybe_emit_vtables):  Always import_export_vtable for the
	reachability analysis.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.3892.2.127&r2=1.3892.2.128
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/decl2.c.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.695.4.8&r2=1.695.4.9



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3/3.4/3.5 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-06-26 10:23 -------
Subject: Bug 14865

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	hubicka@gcc.gnu.org	2004-06-26 10:23:10

Modified files:
	gcc/cp         : ChangeLog decl2.c 

Log message:
	PR C++/14865
	* decl2.c (maybe_emit_vtables):  Always import_export_vtable for the
	reachability analysis.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.4130&r2=1.4131
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/decl2.c.diff?cvsroot=gcc&r1=1.720&r2=1.721



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3 Regression] [no-unit-at-a-time] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to fail|3.3 3.3.1 3.3.2 3.3.3 3.3.4 |3.3 3.3.1 3.3.2 3.3.3 3.3.4
                   |3.4.0 3.5.0                 |3.4.0
      Known to work|3.2.3                       |3.2.3 3.4.1 3.5.0
            Summary|[3.3/3.4/3.5 Regression]    |[3.3 Regression] [no-unit-
                   |[no-unit-at-a-time] No      |at-a-time] No instantiation
                   |instantiation of VTT at -O1 |of VTT at -O1
   Target Milestone|3.4.1                       |3.3.5


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3 Regression] No instantiation of VTT at -O1

[pinskia at gcc dot gnu dot org]

-- 
Bug 14865 depends on bug 15816, which changed state.

Bug 15816 Summary: non-unit-at-a-time should be removed
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15816

           What    |Old Value                   |New Value
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |WONTFIX

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3 Regression] No instantiation of VTT at -O1

[gdr at gcc dot gnu dot org]

------- Additional Comments From gdr at gcc dot gnu dot org  2004-09-28 13:30 -------
Adjust milestone

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
      Known to work|3.2.3 3.4.1 4.0             |3.2.3 3.4.1 4.0.0
   Target Milestone|3.3.5                       |3.3.6


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865

[Bug c++/14865] [3.3 Regression] No instantiation of VTT at -O1

[gdr at gcc dot gnu dot org]

------- Additional Comments From gdr at gcc dot gnu dot org  2005-04-30 13:37 -------
As per comment #10, there is no proposed patch for 3.3.6. Closing as
won't fix..

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|3.3.6                       |3.4.3


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14865