gdb/2497: breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted

gdb/2497: breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted

[dave.anglin]

>Number:         2497
>Category:       gdb
>Synopsis:       breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Sun Aug 10 17:58:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Dave Anglin
>Release:        6.8.50.20080810-cvs
>Organization:
>Environment:
hppa64-hp-hpux11.11
>Description:
int
main ()
{
  return 0;
}

# gcc -o main -g main.c
# gdb/gdb main
GNU gdb (GDB) 6.8.50.20080810-cvs
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "hppa64-hp-hpux11.11".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
(gdb) r
Starting program: /xxx/gnu/gdb/objdir/main 
warning: Private mapping of shared library text was not specified
by the executable; setting a breakpoint in a shared library which
is not privately mapped will not work.  See the HP-UX 11i v3 chatr
manpage for methods to privately map shared library text.
warning: Loadable segment ".tbss" outside of ELF segments
warning: Loadable segment ".tbss" outside of ELF segments

Program exited normally.
(gdb) break main
Breakpoint 1 at 0x4000000000002a38: file main.c, line 4.
../../src/gdb/breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) 

Or,

# gdb/gdb main
GNU gdb (GDB) 6.8.50.20080810-cvs
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "hppa64-hp-hpux11.11".
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>...
(gdb) break main
Breakpoint 1 at 0x4000000000002a38: file main.c, line 4.
(gdb) r
Starting program: /xxx/gnu/gdb/objdir/main 
warning: Private mapping of shared library text was not specified
by the executable; setting a breakpoint in a shared library which
is not privately mapped will not work.  See the HP-UX 11i v3 chatr
manpage for methods to privately map shared library text.
warning: Loadable segment ".tbss" outside of ELF segments
warning: Loadable segment ".tbss" outside of ELF segments

Breakpoint 1, main () at main.c:4
4	  return 0;
(gdb) c
Continuing.

Program exited normally.
(gdb) del 1
../../src/gdb/breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Quit this debugging session? (y or n) 

This problem doesn't seem to be present in 6.8.
>How-To-Repeat:

>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:

Re: gdb/2497: breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted

[John David Anglin]

The following reply was made to PR gdb/2497; it has been noted by GNATS.

From: "John David Anglin" <dave@hiauly1.hia.nrc.ca>
To: gdb-gnats@sources.redhat.com, nobody@sources.redhat.com
Cc: dave.anglin@nrc-cnrc.gc.ca
Subject: Re: gdb/2497: breakpoint.c:4161: internal-error: allegedly permanent breakpoint is not actually inserted
Date: Sun, 10 Aug 2008 15:59:12 -0400 (EDT)

 The problem is with the "permanent" breakpoint __dld_break.
 
 (gdb) bt
 #0  0xc0000000001fb30c in kill () from /lib/pa20_64/libc.2
 #1  0xc0000000001aa6ec in raise () from /lib/pa20_64/libc.2
 #2  0xc0000000001df960 in abort_C () from /lib/pa20_64/libc.2
 #3  0xc0000000001df9c4 in abort () from /lib/pa20_64/libc.2
 #4  0x400000000011d294 in internal_vproblem (problem=0x6300000000000000, file=Cannot access memory at address 0x8
 
 ) at ../../src/gdb/utils.c:780
 #5  0x400000000011d350 in internal_verror (file=Cannot access memory at address 0x0
 ) at ../../src/gdb/utils.c:805
 #6  0x400000000011d3dc in internal_error (file=Cannot access memory at address 0x0
 ) at ../../src/gdb/utils.c:814
 #7  0x40000000001c994c in check_duplicates_for (address=13835058055284211344, 
     section=Cannot access memory at address 0x8
     ) at ../../src/gdb/breakpoint.c:4161
 #8  0x40000000001c9b24 in check_duplicates (bpt=0x60e840d0000fc212)
     at ../../src/gdb/breakpoint.c:4195
 ...
 (gdb) frame 7
 #7  0x40000000001c994c in check_duplicates_for (address=13835058055284211344, 
     section=Cannot access memory at address 0x8
 ) at ../../src/gdb/breakpoint.c:4161
 4161		internal_error (__FILE__, __LINE__,
 (gdb) p/x perm_bp
 $1 = 0x800000010011a530
 (gdb) p/x *perm_bp
 $2 = {next = 0x0, global_next = 0x80000001000e4728, loc_type = 0x0, 
   owner = 0x800000010011a408, cond = 0x0, shlib_disabled = 0x0, 
   enabled = 0x1, inserted = 0x0, duplicate = 0x0, 
   address = 0xc0000000000225fc, length = 0x0, watchpoint_type = 0x0, 
   section = 0x0, requested_address = 0xc0000000000225fc, function_name = 0x0, 
   target_info = {placed_address = 0x0, shadow_contents = {
       0x0 <repeats 16 times>}, shadow_len = 0x0, placed_size = 0x0}, 
   overlay_target_info = {placed_address = 0x0, shadow_contents = {
       0x0 <repeats 16 times>}, shadow_len = 0x0, placed_size = 0x0}, 
   events_till_retirement = 0x0}
 ...
 (gdb) disass 0xc0000000000225fc
 Dump of assembler code for function __dld_break:
 0xc0000000000225f8 <__dld_break+0>:	bv r0(rp)
 0xc0000000000225fc <__dld_break+4>:	break 4,8
 End of assembler dump.
 (gdb) info shared
 From                To                  Syms Read   Shared Object Library
 0xc00000000000add0  0xc0000000000425e4  Yes         /usr/lib/pa20_64/dld.sl
 0x800003fffdf0a1b0  0x800003fffdfe64b0  Yes         /lib/pa20_64/libc.2
 0x800003fffdea9160  0x800003fffdeaa588  Yes         /usr/lib/pa20_64/libdl.1
 0x800003fffdea4574  0x800003fffdea4574  Yes         /opt/graphics/OpenGL/lib/pa20_64/libogltls.sl
 
 The inserted field is set in make_breakpoint_permanent.  However,
 it seems to be getting cleared somewhere.
 
 Dave
 -- 
 J. David Anglin                                  dave.anglin@nrc-cnrc.gc.ca
 National Research Council of Canada              (613) 990-0752 (FAX: 952-6602)