[Bug gdb/15453] New: Free Pascal and Lazarus: Internal-error TYPE_CODE_UNDEF and crash when executing command 'ptype Form1.Test'

[evvke at hotmail dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=15453

Bug #: 15453
Summary: Free Pascal and Lazarus: Internal-error
TYPE_CODE_UNDEF and crash when executing command
'ptype Form1.Test'
Product: gdb
Version: 7.6
Status: NEW
Severity: critical
Priority: P2
Component: gdb
AssignedTo: ***@sourceware.org
ReportedBy: ***@hotmail.com
Classification: Unclassified


Created attachment 7019
--> http://sourceware.org/bugzilla/attachment.cgi?id=7019
Patch for libiberty/xstrdup.c to prevent SIGSEGV.

See http://bugs.freepascal.org/view.php?id=24401 for more information and test
project.

Lazarus uses MI interface to handle debugging process. Attached patch fixes
sudden crash after executing command 'ptype Form1.Test'.

[tromey at redhat dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=15453

Tom Tromey <tromey at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at redhat dot com

--- Comment #1 from Tom Tromey <tromey at redhat dot com> 2013-05-10 01:31:46 UTC ---
Could you get a stack trace from gdb? And, ideally, some simple test
source, plus compilation instructions, that shows the failure?

The patch you sent is definitely not the right fix --
nothing should pass NULL to xstrdup. So the bug must be elsewhere.
Also, from the comments in the upstream bug I don't see how this
could fix it anyhow...

Thanks.

[evvke at hotmail dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=15453

--- Comment #2 from evvke at hotmail dot com 2013-05-10 11:19:50 UTC ---
Backtrace from GDB which are built from 7.6 source.

#0 0x767143f9 in strlen () from C:\windows\syswow64\msvcrt.dll
0000001 0x006470d7 in xstrdup (s=0x0) at ./xstrdup.c:33
0000002 0x0044db2c in mi_cmd_interpreter_exec (
command=0x6c286a <__PRETTY_FUNCTION__.21574+3209> "-interpreter-exec",
argv=0x2a0fc40, argc=2) at ./mi/mi-interp.c:270
0000003 0x004512e2 in captured_mi_execute_command (context=0x311c70,
uiout=0x312740) at ./mi/mi-main.c:1923
0000004 mi_execute_command (cmd=0x6d23960 "ptype Form1.Test", from_tty=1)
at ./mi/mi-main.c:2003
0000005 0x0044c5d4 in mi_execute_command_wrapper (
cmd=0x6d23960 "ptype Form1.Test") at ./mi/mi-interp.c:311
0000006 mi_execute_command_input_handler (cmd=0x6d23960 "ptype Form1.Test")
at ./mi/mi-interp.c:319
0000007 0x004eb0e4 in handle_file_event (data=...) at event-loop.c:768
0000008 0x004eb4df in process_event () at event-loop.c:342
0000009 process_event () at event-loop.c:314
0000010 0x004eb845 in gdb_do_one_event () at event-loop.c:406
0000011 0x004eb997 in start_event_loop () at event-loop.c:431
0000012 0x004e5d22 in captured_command_loop (data=0x0) at main.c:258
0000013 0x004e4a73 in catch_errors (func=0x4e5d10 <captured_command_loop>,
func_args=0x0, errstring=0x6fe967 <__PRETTY_FUNCTION__.11251+213> "",
mask=6) at exceptions.c:546
0000014 0x004e67e9 in captured_main (data=0x2a0feb0) at main.c:1041
0000015 0x004e4a73 in catch_errors (func=0x4e5ed0 <captured_main>,
func_args=0x2a0feb0,
errstring=0x6fe967 <__PRETTY_FUNCTION__.11251+213> "", mask=6)
at exceptions.c:546
0000016 0x004e6de0 in gdb_main (args=0x2a0feb0) at main.c:1050
0000017 0x006a3748 in main (argc=5, argv=0x318a0) at gdb.c:34

These commands were run before executing process:

"maint set internal-error quit no"
"maint set internal-warning quit no"
"maint set internal-error corefile no"

[evvke at hotmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=15453

--- Comment #3 from evvke at hotmail dot com ---
I can't reproduce anymore this bug in 7.7.50.20140112-cvs, git master commit
5acfdbae5d2b0aaa2320ddfa3aa1f2cddce7b978.

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15453

Tom Tromey <tromey at sourceware dot org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
CC| |tromey at sourceware dot org
Component|gdb |pascal
Resolution|--- |FIXED

--- Comment #4 from Tom Tromey <tromey at sourceware dot org> ---
Reported as fixed.