[Bug debug/12103] New: -g only crash (segfault) with a forward declared class used as a template parameter

[Bug debug/12103] New: -g only crash (segfault) with a forward declared class used as a template parameter

[ritzert at t-online dot de]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

           Summary: -g only crash (segfault) with a forward declared class
                    used as a template parameter
           Product: gcc
           Version: 3.4
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: debug
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: ritzert at t-online dot de
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: i686-pc-linux-gnu
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu

The backtrace from cc1plus 
 
#0  0x083d1f3b in host_integerp (t=0x0, pos=0) 
    at /home/ritzert/gcc/HEAD/gcc/gcc/tree.c:3257 
#1  0x083d1fd9 in tree_low_cst (t=0x0, pos=0) 
    at /home/ritzert/gcc/HEAD/gcc/gcc/tree.c:3275 
#2  0x081db313 in add_data_member_location_attribute (die=0x401b0050, 
    decl=0x401a9e40) at /home/ritzert/gcc/HEAD/gcc/gcc/dwarf2out.c:9014 
#3  0x081e1574 in gen_inheritance_die (binfo=0x401a9e40, access=0x0, 
    context_die=0x401b0028) at 
/home/ritzert/gcc/HEAD/gcc/gcc/dwarf2out.c:11191 
 
shows that BINFO_VPTR_FIELD (decl) is 0 in add_data_member_location_attribute. 
 
The stripped down testcase: 
template<class T> 
class foo 
{ 
    T data_; 
}; 
 
class bar; 
typedef foo< bar > foobar; 
 
class obj 
{ 
  virtual foobar* yeah() = 0; 
}; 
 
class bar : virtual public obj 
{ 
}; 
 
gcc version 3.4 20030827 (experimental) 
 
The above code compiles 
- with gcc version 3.3.2 20030812 (Debian prerelease) 
- or without -g

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103


pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |ice-on-valid-code
   Last reconfirmed|0000-00-00 00:00:00         |2003-08-29 13:18:32
               date|                            |
            Summary|-g only crash (segfault)    |[3.4 Regression] -g only
                   |with a forward declared     |crash (segfault) with a
                   |class used as a template    |forward declared class used
                   |parameter                   |as a template parameter
   Target Milestone|---                         |3.4


------- Additional Comments From pinskia at gcc dot gnu dot org  2003-08-29 13:18 -------
I can confirm this on the mainline (20030828).
>From Phil's regression hunter: Search converges between 2002-12-15-trunk (#165) and 2002-
12-16-trunk (#166).  That was the day of the split of the mainline and 3.3 so it should be easier to 
track down what did it (or not because of BIB).

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-11-09 03:16 -------
#2  0x081d1692 in add_data_member_location_attribute (die=0x4012a320, decl=
0x40127e40)    at /home/gates/pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:90349034              
offset = tree_low_cst (BINFO_VPTR_FIELD (decl), 0);(gdb) l9029              /* Extract the 
vtable address.  */9030              tmp = new_loc_descr (DW_OP_deref, 0, 0);9031              
add_loc_descr (&loc_descr, tmp);90329033              /* Calculate the address of the offset.  
*/9034              offset = tree_low_cst (BINFO_VPTR_FIELD (decl), 0);9035              if (offset 
>= 0)9036                abort ();90379038              tmp = int_loc_descriptor (-offset);(gdb) p 
decl$1 = 0x40127e40(gdb) p debug_tree(decl) <tree_vec 0x40127e40    type <
record_type 0x401289b4 obj addressable tree_2 needs-constructing type_1 type_5 BLK        
size <integer_cst 0x4004e9b0 constant 32>        unit size <integer_cst 0x4004ea00 
constant 4>        align 32 symtab 1074963272 alias set -1        fields <field_decl 
0x40129b64 _vptr.obj type <pointer_type 0x400bb654>            unsigned virtual SI file 
pr12103.cc line 11 size <integer_cst 0x4004e9b0 32> unit size <integer_cst 
0x4004ea00 4>            align 32 offset_align 128            offset <integer_cst 0x4004ea14 
constant 0>            bit offset <integer_cst 0x4004eab4 constant 0> context <record_type 
0x401289b4 obj> arguments <integer_cst 0x4004ea14 0> chain <type_decl 
0x40128b64 obj>>       needs-constructor X() X(constX&) this=(X&) n_parents 0 
use_template=0 interface-unknown        member-functions <tree_vec 0x40127c80            
elt 0 <overload 0x4011b880>            elt 2 <function_decl 0x40129654 operator=>            
elt 3 <overload 0x4011b8c0>            elt 4 <overload 0x4011b8a0>            elt 5 <
function_decl 0x40128d14 yeah>>        pointer_to_this <pointer_type 0x40128a8c> 
reference_to_this <reference_type 0x40129438> chain <type_decl 0x40128af8 obj>>    
static tree_4    elt 0 <tree_vec 0x40127a80>    elt 1 <integer_cst 0x4004ea14 0>    elt 3 <
tree_list 0x4012b80c>    elt 9 <tree_vec 0x40127a80>>$2 = void

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|2003-08-29 13:18:32         |2003-11-09 03:16:26
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2003-12-19 05:42 -------
Here is the full backtrace:
#0  0x083aa7fb in host_integerp (t=0x0, pos=0) at /home/gates/pinskia/src/gnu/gcc/src/gcc/
tree.c:3285
#1  0x083aa899 in tree_low_cst (t=0x0, pos=0) at /home/gates/pinskia/src/gnu/gcc/src/gcc/
tree.c:3303
#2  0x081d5942 in add_data_member_location_attribute (die=0x4012a320, decl=0x40127ec0) at 
/home/gates/pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:9054
#3  0x081da319 in gen_type_die (type=0x4012857c, context_die=0x400b5ed8) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:11243
#4  0x081d8a94 in gen_decl_die (decl=0x4012d948, context_die=0x400b5ed8) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:10170
#5  0x081da8d0 in gen_type_die (type=0x4012872c, context_die=0x400b5dc0) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:11301
#6  0x081d8d99 in gen_decl_die (decl=0x40128870, context_die=0x400b5dc0) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/dwarf2out.c:12004
#7  0x083a2909 in rest_of_type_compilation (type=0x4012872c, toplev=1) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/toplev.c:2024
#8  0x080cdab6 in finish_struct_1 (t=0x4012872c) at /home/gates/pinskia/src/gnu/gcc/src/gcc/
cp/class.c:5200
#9  0x080acda9 in instantiate_class_template (type=0x4012872c) at /home/gates/pinskia/src/
gnu/gcc/src/gcc/cp/pt.c:5583
#10 0x080f7d7e in complete_type (type=0x4012872c) at /home/gates/pinskia/src/gnu/gcc/src/
gcc/cp/typeck.c:135
#11 0x0811ddc4 in lookup_base (t=0x40128948, base=0x40128948, access=6, 
kind_ptr=0xbffebed4) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/search.c:290
#12 0x080c5269 in dfs_modify_vtables (binfo=0x40127ec0, data=0x4012857c) at /home/gates/
pinskia/src/gnu/gcc/src/gcc/cp/class.c:2199
#13 0x0811d0b8 in dfs_walk_real (binfo=0x40127ec0, prefn=0, postfn=0x80c4ba0 
<dfs_modify_vtables>, qfn=0x8120dc0 <unmarkedp>, data=0x4012857c)
    at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/search.c:1670
#14 0x0811d090 in dfs_walk_real (binfo=0x40127b00, prefn=0, postfn=0x80c4ba0 
<dfs_modify_vtables>, qfn=0x8120dc0 <unmarkedp>, data=0x4012857c)
    at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/search.c:1661
#15 0x0811d20c in dfs_walk (binfo=0x0, fn=0, qfn=0, data=0x0) at /home/gates/pinskia/src/
gnu/gcc/src/gcc/cp/search.c:1684
#16 0x080cc297 in finish_struct_1 (t=0x4012857c) at /home/gates/pinskia/src/gnu/gcc/src/gcc/
cp/class.c:2379
#17 0x080d1537 in finish_struct (t=0x4012857c, attributes=0x0) at /home/gates/pinskia/src/
gnu/gcc/src/gcc/cp/class.c:5258
#18 0x080ea766 in cp_parser_type_specifier (parser=0x40127900, flags=1074967388, 
is_friend=false, is_declaration=true, declares_class_or_enum=0xbffec114,
    is_cv_qualifier=0x0) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/parser.c:11499
#19 0x080ec06e in cp_parser_decl_specifier_seq (parser=0x40127900, 
flags=CP_PARSER_FLAGS_OPTIONAL, attributes=0xbffec148, declares_class_or_enum=0xbffec14c)
    at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/parser.c:6632
#20 0x080ec362 in cp_parser_simple_declaration (parser=0x40127900, 
function_definition_allowed_p=true) at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/parser.c:
6362
#21 0x080ec518 in cp_parser_block_declaration (parser=0x40127900, statement_p=false) at /
home/gates/pinskia/src/gnu/gcc/src/gcc/cp/parser.c:6322
#22 0x080f1d9f in cp_parser_declaration (parser=0x40127900) at /home/gates/pinskia/src/gnu/
gcc/src/gcc/cp/parser.c:6242
#23 0x080f205f in cp_parser_declaration_seq_opt (parser=0x40127900) at /home/gates/pinskia/
src/gnu/gcc/src/gcc/cp/parser.c:6151
#24 0x080f2217 in c_parse_file () at /home/gates/pinskia/src/gnu/gcc/src/gcc/cp/parser.c:2299
#25 0x0817e91e in c_common_parse_file (set_yydebug=0) at /home/gates/pinskia/src/gnu/gcc/
src/gcc/c-opts.c:1227
#26 0x083a608d in toplev_main (argc=0, argv=0xbffec59b) at /home/gates/pinskia/src/gnu/gcc/
src/gcc/toplev.c:1804
#27 0x081821ae in main (argc=0, argv=0x0) at /home/gates/pinskia/src/gnu/gcc/src/gcc/
main.c:35

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-05 08:47 -------
This is definitely when the BIB went in so someone has to do a hunt on that branch.

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|critical                    |normal


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[pinskia at gcc dot gnu dot org]

------- Additional Comments From pinskia at gcc dot gnu dot org  2004-01-16 02:36 -------
I have found out that this started to happen between 12-1-2002 and 12-12-2002 (all at 
midnite GMT).  I will be trying to narrow down the date but the only patch to c++ between 
this point was the one which implemented covariant returns.  Nathan could you look into 
this because I think it was your patch.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |nathan at gcc dot gnu dot
                   |                            |org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4/3.5 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[mmitchel at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |mark at codesourcery dot com
                   |dot org                     |
             Status|NEW                         |ASSIGNED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4/3.5 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-02-29 23:04 -------
Subject: Bug 12103

CVSROOT:	/cvs/gcc
Module name:	gcc
Branch: 	gcc-3_4-branch
Changes by:	mmitchel@gcc.gnu.org	2004-02-29 23:04:14

Modified files:
	gcc/cp         : ChangeLog class.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/g++.dg/debug: crash1.C 

Log message:
	PR debug/12103
	* class.c (update_vtable_entry_for_fn): Do not go through
	covariance machinery if the type returned by an overrider is the
	same as the original.
	
	PR debug/12103
	* g++.dg/debug/crash1.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.3892.2.62&r2=1.3892.2.63
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/class.c.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.595.4.5&r2=1.595.4.6
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=1.3389.2.112&r2=1.3389.2.113
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/debug/crash1.C.diff?cvsroot=gcc&only_with_tag=gcc-3_4-branch&r1=NONE&r2=1.1.2.1



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4/3.5 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[cvs-commit at gcc dot gnu dot org]

------- Additional Comments From cvs-commit at gcc dot gnu dot org  2004-02-29 23:10 -------
Subject: Bug 12103

CVSROOT:	/cvs/gcc
Module name:	gcc
Changes by:	mmitchel@gcc.gnu.org	2004-02-29 23:10:44

Modified files:
	gcc/cp         : ChangeLog class.c 
	gcc/testsuite  : ChangeLog 
Added files:
	gcc/testsuite/g++.dg/debug: crash1.C 

Log message:
	PR debug/12103
	* class.c (update_vtable_entry_for_fn): Do not go through
	covariance machinery if the type returned by an overrider is the
	same as the original.
	
	PR debug/12103
	* g++.dg/debug/crash1.C: New test.

Patches:
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/ChangeLog.diff?cvsroot=gcc&r1=1.3975&r2=1.3976
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/cp/class.c.diff?cvsroot=gcc&r1=1.601&r2=1.602
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/ChangeLog.diff?cvsroot=gcc&r1=1.3556&r2=1.3557
http://gcc.gnu.org/cgi-bin/cvsweb.cgi/gcc/gcc/testsuite/g++.dg/debug/crash1.C.diff?cvsroot=gcc&r1=1.1&r2=1.2



-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103

[Bug debug/12103] [3.4/3.5 Regression] -g only crash (segfault) with a forward declared class used as a template parameter

[mmitchel at gcc dot gnu dot org]

------- Additional Comments From mmitchel at gcc dot gnu dot org  2004-02-29 23:17 -------
Fixed in GCC 3.4 and GCC 3.5.

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|                            |FIXED


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12103