[Bug mi/10758] New: -var-list-children hangs

[Bug mi/10758] New: -var-list-children hangs

[andre dot poenitz at nokia dot com]

I get reproducible hangs of 7.0's  -var-list-children.

When I attach to 7.0 using 6.8 at the time it hangs I get the following backtrace:

This GDB was configured as "i486-linux-gnu".
Attaching to process 24700
Reading symbols from /home/apoenitz/debugger/gdb-7.0/gdb/gdb...done.
Reading symbols from /lib/libncurses.so.5...done.
Loaded symbols for /lib/libncurses.so.5
Reading symbols from /lib/libz.so.1...done.
Loaded symbols for /lib/libz.so.1
Reading symbols from /lib/tls/i686/cmov/libm.so.6...done.
Loaded symbols for /lib/tls/i686/cmov/libm.so.6
Reading symbols from /usr/lib/libpython2.6.so.1.0...done.
Loaded symbols for /usr/lib/libpython2.6.so.1.0
Reading symbols from /usr/local/lib/libexpat.so.1...done.
Loaded symbols for /usr/local/lib/libexpat.so.1
Reading symbols from /lib/tls/i686/cmov/libdl.so.2...done.
Loaded symbols for /lib/tls/i686/cmov/libdl.so.2
Reading symbols from /lib/tls/i686/cmov/libc.so.6...done.
Loaded symbols for /lib/tls/i686/cmov/libc.so.6
Reading symbols from /lib/ld-linux.so.2...done.
Loaded symbols for /lib/ld-linux.so.2
Reading symbols from /lib/tls/i686/cmov/libpthread.so.0...done.
[Thread debugging using libthread_db enabled]
[New Thread 0xb7b0f8d0 (LWP 24700)]
Loaded symbols for /lib/tls/i686/cmov/libpthread.so.0
Reading symbols from /lib/tls/i686/cmov/libutil.so.1...done.
Loaded symbols for /lib/tls/i686/cmov/libutil.so.1
Reading symbols from /lib/tls/i686/cmov/libthread_db.so.1...done.
Loaded symbols for /lib/tls/i686/cmov/libthread_db.so.1
0x08130839 in value_primitive_field (arg1=0xa234f00, offset=0, fieldno=4, 
    arg_type=0x99094a8) at value.c:1892
1892          if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize
(gdb) bt full
#0  0x08130839 in value_primitive_field (arg1=0xa234f00, offset=0, fieldno=4, 
    arg_type=0x99094a8) at value.c:1892
        bitpos = 128
        container_bitsize = 0
        v = (struct value *) 0x950b3f8
        type = (struct type *) 0x990952c
#1  0x081ddf41 in value_struct_element_index (value=0xa234f00, type_index=4)
    at varobj.c:2747
        result = (struct value *) 0x0
        e = {reason = 0, error = GDB_NO_ERROR, message = 0x0}
        type = (struct type *) 0x99094a8
        __PRETTY_FUNCTION__ = "value_struct_element_index"
#2  0x081de6c0 in cplus_describe_child (parent=<value optimized out>, index=-1, 
    cname=0x0, cvalue=0xbffb7d24, ctype=0x0, cfull_expression=0x0) at varobj.c:3222
        type_index = 4
        acc = <value optimized out>
        join = 0x82fea65 "."
        value = (struct value *) 0xa234f00
        type = (struct type *) 0x99094a8
        was_ptr = 0
        parent_expression = 0x0
        __PRETTY_FUNCTION__ = "cplus_describe_child"
#3  0x081de7d0 in cplus_value_of_child (parent=0xb6cd838, index=4) at varobj.c:3344
        value = (struct value *) 0x0
#4  0x081e1b50 in varobj_list_children (var=0xb6cd838, from=0xbffb7d98, 
    to=0xbffb7d94) at varobj.c:2429
        existing = <value optimized out>
        name = 0x950b3e8 "sharable"
        i = 4
        children_changed = 5003
#5  0x080f2dab in mi_cmd_var_list_children (command=0xb6cd898 "var-list-children", 
    argv=0xb9827a8, argc=2) at ./mi/mi-cmd-var.c:423
        var = (struct varobj *) 0xb6cd838
        children = <value optimized out>
        child = <value optimized out>
        print_values = <value optimized out>
        ix = <value optimized out>
        from = -1
        to = -1
        display_hint = <value optimized out>
#6  0x080f6523 in captured_mi_execute_command (uiout=0x9478b50, data=0x94eaa00)
    at ./mi/mi-main.c:1388
        cleanup = (struct cleanup *) 0x0
#7  0x081713ca in catch_exception (uiout=0x9478b50, 
    func=0x80f63e0 <captured_mi_execute_command>, func_args=0x94eaa00, mask=6)
    at exceptions.c:462
        exception = {reason = 0, error = GDB_NO_ERROR, message = 0x0}
#8  0x080f608b in mi_execute_command (
    cmd=0xa4a7650 "240-var-list-children --all-values
\"local.list.myns::QList<myns::QString>.@.d.*.public\"", from_tty=1) at
./mi/mi-main.c:1288
        result = {reason = 160, error = 172652112, 
  message = 0xbffb7e78 "\230~&#65533;004i\027\bPvJ\n"}
        previous_ptid = {pid = 24703, lwp = 24703, tid = 0}
        command = (struct mi_parse *) 0x94eaa00

-- 
           Summary: -var-list-children hangs
           Product: gdb
           Version: 6.8
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: mi
        AssignedTo: unassigned at sourceware dot org
        ReportedBy: andre dot poenitz at nokia dot com
                CC: gdb-prs at sourceware dot org
 GCC build triplet: i486-linux-gnu
  GCC host triplet: i486-linux-gnu
GCC target triplet: i486-linux-gnu


http://sourceware.org/bugzilla/show_bug.cgi?id=10758

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.

[Bug mi/10758] -var-list-children hangs

[andre dot poenitz at nokia dot com]

------- Additional Comments From andre dot poenitz at nokia dot com  2009-10-12 09:13 -------

Seems like a division by zero is involved:

(gdb) step

Program received signal SIGFPE, Arithmetic exception.
[Switching to Thread 0xb7b0f8d0 (LWP 24700)]
0x08130839 in value_primitive_field (arg1=0xa234f00, offset=0, fieldno=4, 
    arg_type=0x99094a8) at value.c:1892
1892          if ((bitpos % container_bitsize) + v->bitsize <= container_bitsize
(gdb) p container_bitsize
$1 = 0
(gdb) 

-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=10758

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.

[Bug mi/10758] -var-list-children hangs

[vladimir at codesourcery dot com]

------- Additional Comments From vladimir at codesourcery dot com  2009-10-22 06:45 -------
What kind of value is being examined when this problem happens? Can you 
provide full definition of relevant types?

-- 


http://sourceware.org/bugzilla/show_bug.cgi?id=10758

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.

[Bug mi/10758] -var-list-children hangs

[tromey at redhat dot com]

------- Additional Comments From tromey at redhat dot com  2009-12-02 20:35 -------
10884 has more details, so I'm closing this one.

*** This bug has been marked as a duplicate of 10884 ***

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


http://sourceware.org/bugzilla/show_bug.cgi?id=10758

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.