Breakpoints for .so in gdb 6.6 latest version do not work

[Neo <cjia at cse dot unl dot edu>]

hi,

When I am trying to use the latest version gdb (GNU gdb 
6.6.0.20070202-cvs) to debug Sun hotspot vm, it cannot break the code 
inside libjvm.so any more. Because I am using the latest kernel from 
git, I even try the old version gdb (6.5.50.20060621-cvs) on the same 
platform, which works very well. And I also try these two versions gdb 
on 2.6.9-1.667smp, still the latest gdb cannot work.

So, I am afraid that this might be a bug. The following is the log file. 
If you need more information, please let me know.

=============[ GDB 6.5, working version ]=============

-------[ kernel 2.6.20-rc6 ]----------

> ~/downloads/gdb-cvs/gdb/gdb java_g
GNU gdb 6.5.50.20060621-cvs
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you 
are
welcome to change it and/or distribute copies of it under certain 
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...Using host libthread_db 
library "/lib/tls/libthread_db.so.1".

(gdb) b genMarkSweep.cpp:307
No source file named genMarkSweep.cpp.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (genMarkSweep.cpp:307) pending.
(gdb) r -XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap -Xms96m 
-Xmx96m -cp .:/spec/jvm98 -Dinstall.root=/spec/jvm98/ SpecApplication 
_202_jess
Starting program: 
/home/cjia/research/jdk/jdk5_svn/control/build/linux-i586/bin/java_g 
-XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap -Xms96m -Xmx96m 
-cp .:/spec/jvm98 -Dinstall.root=/spec/jvm98/ SpecApplication _202_jess
[Thread debugging using libthread_db enabled]
[New Thread -1208973632 (LWP 21967)]
[New process 21967]
Executing new program: 
/home/cjia/research/jdk/jdk5_svn/control/build/linux-i586/bin/java_g
[Thread debugging using libthread_db enabled]
[New Thread -1208448800 (LWP 21967)]
Breakpoint 2 at 0xb772027d: file 
/home/cjia/research/jdk/jdk5_svn/hotspot/src/share/vm/memory/genMarkSweep.cpp, 
line 307.
Pending breakpoint "genMarkSweep.cpp:307" resolved
VM option '+DebugCompPoint'
VM option '+MonitorCompaction'
========================Heap Summary Begin========================
167772160 bytes, from [0xaae30000] to [0xb4e30000]
------------------------Heap details------------------------
Heap[0] init. size = 7733248 bytes max. size = 7733248 bytes.
eden space size 6291456, bottom 0xaae30000, end 0xab430000
from space size 720896, bottom 0xab430000, end 0xab4e0000
to space size 720896, bottom 0xab4e0000, end 0xab590000
Heap[1] init. size = 92930048 bytes max. size = 92930048 bytes.
tenure space size 92930048, bottom 0xab590000, end 0xb0e30000
Perm. init. size = 8388608 bytes max. size = 67108864 bytes.

========================Heap Summary End ========================
[New Thread -1428780112 (LWP 21972)]
[New Thread -1429308496 (LWP 21973)]
[New Thread -1429836880 (LWP 21974)]
[New Thread -1432462416 (LWP 21975)]
[New Thread -1432990800 (LWP 21976)]
[New Thread -1433519184 (LWP 21977)]
[New Thread -1434047568 (LWP 21978)]
[Switching to Thread -1428780112 (LWP 21972)]
Breakpoint 2, GenMarkSweep::mark_sweep_phase2 () at 
/home/cjia/research/jdk/jdk5_svn/hotspot/src/share/vm/memory/genMarkSweep.cpp:307
307       GenCollectedHeap* gch = GenCollectedHeap::heap();
Current language:  auto; currently c++

------[ kernel 2.6.9 ]----------

> ~/downloads/gdb-cvs/gdb/gdb java_g
GNU gdb 6.5.50.20060621-cvs
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain 
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...Using host libthread_db 
library "/lib/tls/libthread_db.so.1".

(gdb) b genMarkSweep.cpp:307
No source file named genMarkSweep.cpp.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (genMarkSweep.cpp:307) pending.
(gdb) r -XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap -Xms96m 
-Xmx96m -cp .:/spec/jvm98 -Dinstall.root=/spec/jvm98/ SpecApplication 
_202_jess
Starting program: 
/home/cjia/research/jdk/jdk5_svn/control/build/linux-i586/bin/java_g 
-XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap -Xms96m -Xmx96m 
-cp .:/spec/jvm98 -Dinstall.root=/spec/jvm98/ SpecApplication _202_jess
[Thread debugging using libthread_db enabled]
[New Thread -151103808 (LWP 3892)]
[New process 3892]
Executing new program: 
/home/cjia/research/jdk/jdk5_svn/control/build/linux-i586/bin/java_g
[Thread debugging using libthread_db enabled]
[New Thread -151103808 (LWP 3892)]
Breakpoint 2 at 0xf677d27d: file 
/home/cjia/research/jdk/jdk5_svn/hotspot/src/share/vm/memory/genMarkSweep.cpp, 
line 307.
Pending breakpoint "genMarkSweep.cpp:307" resolved
VM option '+DebugCompPoint'
VM option '+MonitorCompaction'
========================Heap Summary Begin========================
167772160 bytes, from [0xe9e70000] to [0xf3e70000]
------------------------Heap details------------------------
Heap[0] init. size = 7733248 bytes max. size = 7733248 bytes.
eden space size 6291456, bottom 0xe9e70000, end 0xea470000
from space size 720896, bottom 0xea470000, end 0xea520000
to space size 720896, bottom 0xea520000, end 0xea5d0000
Heap[1] init. size = 92930048 bytes max. size = 92930048 bytes.
tenure space size 92930048, bottom 0xea5d0000, end 0xefe70000
Perm. init. size = 8388608 bytes max. size = 67108864 bytes.

========================Heap Summary End ========================
[New Thread -371553360 (LWP 3895)]
[New Thread -372081744 (LWP 3896)]
[New Thread -372610128 (LWP 3897)]
[New Thread -375235664 (LWP 3898)]
[New Thread -375764048 (LWP 3899)]
[New Thread -376292432 (LWP 3900)]
[New Thread -376820816 (LWP 3901)]
[Switching to Thread -371553360 (LWP 3895)]
Breakpoint 2, GenMarkSweep::mark_sweep_phase2 () at 
/home/cjia/research/jdk/jdk5_svn/hotspot/src/share/vm/memory/genMarkSweep.cpp:307
307       GenCollectedHeap* gch = GenCollectedHeap::heap();
Current language:  auto; currently c++

=============[ GDB 6.6, failed version ]=============

------[ 2.6.20-rc6 ]-----------

> /home/cjia/research/gdb-6.6-cvs.official/build/gdb/gdb java_g
GNU gdb 6.6.0.20070202-cvs
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you 
are
welcome to change it and/or distribute copies of it under certain 
conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i686-pc-linux-gnu"...
Using host libthread_db library "/lib/tls/libthread_db.so.1".
(gdb) b genMarkSweep.cpp:307
No source file named genMarkSweep.cpp.
Make breakpoint pending on future shared library load? (y or [n]) y
Breakpoint 1 (genMarkSweep.cpp:307) pending.
(gdb) r -XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap 
-XdynamicHeap:rev_comp -Xms96m -Xmx96m -cp .:/spec/jvm98 
-Dinstall.root=/spec/jvm98/ SpecApplication _202_jess
Starting program: 
/home/cjia/research/jdk/jdk5_svn/control/build/linux-i586/bin/java_g 
-XX:+DebugCompPoint -XX:+MonitorCompaction -XmonitorHeap 
-XdynamicHeap:rev_comp -Xms96m -Xmx96m -cp .:/spec/jvm98 
-Dinstall.root=/spec/jvm98/ SpecApplication _202_jess
[Thread debugging using libthread_db enabled]
[New Thread -1208817984 (LWP 5189)]
[New process 5189]
VM option '+DebugCompPoint'
VM option '+MonitorCompaction'
========================Heap Summary Begin========================
167772160 bytes, from [0xaae50000] to [0xb4e50000]
>>>>> Using Dynamic Heap (REVERSE COMPACTION HEAP) <<<<<
------------------------Heap details------------------------
Heap[0] init. size = 7733248 bytes max. size = 7733248 bytes.
eden space size 6291456, bottom 0xaae50000, end 0xab450000
from space size 720896, bottom 0xab450000, end 0xab500000
to space size 720896, bottom 0xab500000, end 0xab5b0000
Heap[1] init. size = 92930048 bytes max. size = 92930048 bytes.
tenure space size 92930048, bottom 0xab5b0000, end 0xb0e50000
Perm. init. size = 8388608 bytes max. size = 67108864 bytes.
.......... (the program will continue running ...)

Thanks,
Neo

--
I would remember that if researchers were not ambitious
probably today we haven't the technology we are using!