public inbox for cygwin@cygwin.com
 help / color / mirror / Atom feed
* gdb broken inside emacs (again? still?)
@ 2011-11-09 21:44 Ryan Johnson
  2011-11-09 22:32 ` Ken Brown
  0 siblings, 1 reply; 6+ messages in thread
From: Ryan Johnson @ 2011-11-09 21:44 UTC (permalink / raw)
  To: cygwin

Hi all,

Attempting to run gdb inside emacs with an executable file name argument 
(with or without --annotate=3) causes it to seg fault (no surprise, 
known issue). Running just `gdb' from emacs allows it to initialize, but 
attempts to load a file or indeed perform any command hang until a 
double-^C cancels the attempt (reporting "C-c C-cquit"). Ironically, 
even `quit' hangs, so you have to use ^D to exit. Debugging anything 
within emacs is thus completely impossible at this time. I've tried with 
a home-compiled gdb (same version) with no better luck. I'm building an 
emacs-23 from scratch, but I'm pretty sure I've already tried that 
before, without any conclusive improvement.

I know this has come up before, and that it has been "resolved" before 
for me and for others, but it keeps recurring (usually whenever I 
actually need to debug something) and I can't find any reliable way to 
make the problem go away.

Do the latest snapshots contain changes which should fix the problem?

I'm on an win7-64 system, running the 13 Oct dll snapshot, after a 
rebaseall. Relevant package versions are below (setup.exe doesn't 
advertize any newer ones):
> binutils                    2.22.51-1
> gcc4                        4.5.3-3
> gcc4-core                   4.5.3-3
> gcc4-g++                    4.5.3-3
> gcc4-java                   4.5.3-3
> gdb                         7.3.50-2
> emacs                       23.3-3
> emacs-X11                   23.3-3

Thanks,
Ryan



--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: gdb broken inside emacs (again? still?)
  2011-11-09 21:44 gdb broken inside emacs (again? still?) Ryan Johnson
@ 2011-11-09 22:32 ` Ken Brown
  2011-11-09 23:08   ` Ryan Johnson
  2011-11-09 23:59   ` Ryan Johnson
  0 siblings, 2 replies; 6+ messages in thread
From: Ken Brown @ 2011-11-09 22:32 UTC (permalink / raw)
  To: cygwin

On 11/9/2011 4:44 PM, Ryan Johnson wrote:
> Hi all,
>
> Attempting to run gdb inside emacs with an executable file name argument
> (with or without --annotate=3) causes it to seg fault (no surprise,
> known issue). Running just `gdb' from emacs allows it to initialize, but
> attempts to load a file or indeed perform any command hang until a
> double-^C cancels the attempt (reporting "C-c C-cquit"). Ironically,
> even `quit' hangs, so you have to use ^D to exit. Debugging anything
> within emacs is thus completely impossible at this time. I've tried with
> a home-compiled gdb (same version) with no better luck. I'm building an
> emacs-23 from scratch, but I'm pretty sure I've already tried that
> before, without any conclusive improvement.
>
> I know this has come up before, and that it has been "resolved" before
> for me and for others, but it keeps recurring (usually whenever I
> actually need to debug something) and I can't find any reliable way to
> make the problem go away.
>
> Do the latest snapshots contain changes which should fix the problem?
>
> I'm on an win7-64 system, running the 13 Oct dll snapshot, after a
> rebaseall. Relevant package versions are below (setup.exe doesn't
> advertize any newer ones):
>> binutils 2.22.51-1
>> gcc4 4.5.3-3
>> gcc4-core 4.5.3-3
>> gcc4-g++ 4.5.3-3
>> gcc4-java 4.5.3-3
>> gdb 7.3.50-2
>> emacs 23.3-3
>> emacs-X11 23.3-3

cgf has already stated that this will be fixed in the next release of 
gdb; see

   http://cygwin.com/ml/cygwin/2011-10/msg00564.html

In the meantime, can't you use gdb 7.3.50-1?  If you also have problems 
with that release, please send detailed instructions for reproducing the 
problem (starting with emacs -Q).

Ken

P.S. If you're building your own emacs and using a Cygwin snapshot, 
you'll need to apply my patch to fix the memory allocation problem that 
we discussed a few months ago.  You can get this by using setup.exe to 
download the source for emacs-23.3-3.


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: gdb broken inside emacs (again? still?)
  2011-11-09 22:32 ` Ken Brown
@ 2011-11-09 23:08   ` Ryan Johnson
  2011-11-10  2:38     ` Ken Brown
  2011-11-09 23:59   ` Ryan Johnson
  1 sibling, 1 reply; 6+ messages in thread
From: Ryan Johnson @ 2011-11-09 23:08 UTC (permalink / raw)
  To: cygwin

On 09/11/2011 5:32 PM, Ken Brown wrote:
> On 11/9/2011 4:44 PM, Ryan Johnson wrote:
>> Debugging anything within emacs is thus completely impossible at this 
>> time.
>
> cgf has already stated that this will be fixed in the next release of 
> gdb; see
>
>   http://cygwin.com/ml/cygwin/2011-10/msg00564.html
>
Sorry, must have missed that one. Thanks for pointing me at it.

> In the meantime, can't you use gdb 7.3.50-1?  If you also have 
> problems with that release, please send detailed instructions for 
> reproducing the problem (starting with emacs -Q).
No luck:

$ cygcheck -cd | grep gdb
gdb                         7.3.50-1
libgdbm4                    1.8.3-20
$ emacs -Q -nw
M-x gdb
Run gdb (like this): gdb
(gdb) quit
... long time passes...
  C-c C-cQuit
(gdb) ^D
Debugger finished

> P.S. If you're building your own emacs and using a Cygwin snapshot, 
> you'll need to apply my patch to fix the memory allocation problem 
> that we discussed a few months ago.  You can get this by using 
> setup.exe to download the source for emacs-23.3-3.
That would explain why emacs-bootstrap.exe keeps hanging. I'll try 
building from the patched source tree and see what happens.

Ryan


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: gdb broken inside emacs (again? still?)
  2011-11-09 22:32 ` Ken Brown
  2011-11-09 23:08   ` Ryan Johnson
@ 2011-11-09 23:59   ` Ryan Johnson
  1 sibling, 0 replies; 6+ messages in thread
From: Ryan Johnson @ 2011-11-09 23:59 UTC (permalink / raw)
  To: cygwin

On 09/11/2011 5:32 PM, Ken Brown wrote:
> On 11/9/2011 4:44 PM, Ryan Johnson wrote:
>> Running just `gdb' from emacs allows it to initialize, but
>> attempts to load a file or indeed perform any command hang until a
>> double-^C cancels the attempt (reporting "C-c C-cquit"). Ironically,
>> even `quit' hangs, so you have to use ^D to exit. Debugging anything
>> within emacs is thus completely impossible at this time.
> cgf has already stated that this will be fixed in the next release of 
> gdb; see
>
>   http://cygwin.com/ml/cygwin/2011-10/msg00564.html
Hmm. After dwelling longer on the above post chain... I think cgf was 
only talking about fixing the seg fault. Is this freezing somehow 
related? I didn't think it was.

> P.S. If you're building your own emacs and using a Cygwin snapshot, 
> you'll need to apply my patch to fix the memory allocation problem 
> that we discussed a few months ago.  You can get this by using 
> setup.exe to download the source for emacs-23.3-3.
Built, but unfortunately no improvement in behavior by gdb. Is there 
some possibility those cygwin-specific patches somehow are tied up in 
this? The last time this came up a home-built emacs worked with 
gdb-7.3.50-1.

As others have reported, gud-gdb can load and run binaries, but then 
emacs doesn't sync up its output with source files any more...

BTW, I don't know if this has anything to do with anything, but `strace 
gdb' from the command prompt or inside emacs reports an infinite stream 
of seg faults:
>    25 1231358 [main] gdb 4112 __set_errno: void san::leave():277 val 14
> --- Process 4112, exception C0000005 at 6111AE63
>    71 1231429 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler exc 0xC0000005 at 0x6111AE63 sp 0x149C8F4
>    67 1231496 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler sig 11 at 0x6111AE63
>    82 1231578 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler calling 0x0
>    29 1231607 [main] gdb 4112 __set_errno: void san::leave():277 val 14
> --- Process 4112, exception C0000005 at 6111AE63
>    75 1231682 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler exc 0xC0000005 at 0x6111AE63 sp 0x149C8F4
>    28 1231710 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler sig 11 at 0x6111AE63
>    28 1231738 [main] gdb 4112 exception::handle: In 
> cygwin_except_handler calling 0x0

^C kills the program, but attempting to type any other character hangs 
gdb, strace, and the terminal for good measure.

Is gdb just known-unfriendly to strace?

Ryan


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: gdb broken inside emacs (again? still?)
  2011-11-09 23:08   ` Ryan Johnson
@ 2011-11-10  2:38     ` Ken Brown
  2011-11-10  3:23       ` Ryan Johnson
  0 siblings, 1 reply; 6+ messages in thread
From: Ken Brown @ 2011-11-10  2:38 UTC (permalink / raw)
  To: cygwin

On 11/9/2011 6:08 PM, Ryan Johnson wrote:
> On 09/11/2011 5:32 PM, Ken Brown wrote:
>> On 11/9/2011 4:44 PM, Ryan Johnson wrote:
>>> Debugging anything within emacs is thus completely impossible at this
>>> time.
>>
>> cgf has already stated that this will be fixed in the next release of
>> gdb; see
>>
>> http://cygwin.com/ml/cygwin/2011-10/msg00564.html
>>
> Sorry, must have missed that one. Thanks for pointing me at it.
>
>> In the meantime, can't you use gdb 7.3.50-1? If you also have problems
>> with that release, please send detailed instructions for reproducing
>> the problem (starting with emacs -Q).
> No luck:
>
> $ cygcheck -cd | grep gdb
> gdb 7.3.50-1
> libgdbm4 1.8.3-20
> $ emacs -Q -nw
> M-x gdb
> Run gdb (like this): gdb
                        ^^^^^^^^^

That's your problem.  You've deleted `--annotate=3' from the prompt 
emacs gave you.  emacs-23 needs that to be there.  M-x gdb works fine 
for me like that, using both gdb 7.3.50-1 and 7.3.50-3 (which is now 
available).  I tested with Cygwin 1.7.9 as well as with the latest snapshot.

Ken


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: gdb broken inside emacs (again? still?)
  2011-11-10  2:38     ` Ken Brown
@ 2011-11-10  3:23       ` Ryan Johnson
  0 siblings, 0 replies; 6+ messages in thread
From: Ryan Johnson @ 2011-11-10  3:23 UTC (permalink / raw)
  To: cygwin

On 09/11/2011 9:37 PM, Ken Brown wrote:
> On 11/9/2011 6:08 PM, Ryan Johnson wrote:
>> On 09/11/2011 5:32 PM, Ken Brown wrote:
>>> In the meantime, can't you use gdb 7.3.50-1? If you also have problems
>>> with that release, please send detailed instructions for reproducing
>>> the problem (starting with emacs -Q).
>> No luck:
>>
>> $ cygcheck -cd | grep gdb
>> gdb 7.3.50-1
>> libgdbm4 1.8.3-20
>> $ emacs -Q -nw
>> M-x gdb
>> Run gdb (like this): gdb
>                        ^^^^^^^^^
>
> That's your problem.  You've deleted `--annotate=3' from the prompt 
> emacs gave you.  emacs-23 needs that to be there.  M-x gdb works fine 
> for me like that, using both gdb 7.3.50-1 and 7.3.50-3 (which is now 
> available).  I tested with Cygwin 1.7.9 as well as with the latest 
> snapshot.
!!

That was it. Thanks a lot, and sorry for the bother.

Ryan


--
Problem reports:       http://cygwin.com/problems.html
FAQ:                   http://cygwin.com/faq/
Documentation:         http://cygwin.com/docs.html
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2011-11-10  3:23 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2011-11-09 21:44 gdb broken inside emacs (again? still?) Ryan Johnson
2011-11-09 22:32 ` Ken Brown
2011-11-09 23:08   ` Ryan Johnson
2011-11-10  2:38     ` Ken Brown
2011-11-10  3:23       ` Ryan Johnson
2011-11-09 23:59   ` Ryan Johnson

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).