Emacs - MinGW32 on W2K

Emacs - MinGW32 on W2K

[Dhruva Krishnamurthy]

Hello,

To GCC bug track (person I have CC'ed):
other/9816: GCC 3.2.2 (Mingw Release candidate version) - Regression in
building GNU Emacs 21.3 (CVS) 

 I did some further testing. I am building GNU Emacs using various
 versions of GCC on MinGW32 (W2K) and also MSVC
I have tried GCC 3.2.1, GCC 3.2.2 and GCC 3.3

This happens on both Emacs 21.3 and Emacs 21.2.95

A reproducible recepie for a crash:
- Launch emacs
- Load library "recentf" (load-library "recentf")
- Set the recentf mode (recentf-mode t)
- M-x recentf-open-files
CRASH (Emacs Abort Dialog: A fatal error has occured!)

Next:
- Remove the "lisp/wid-edit.elc" file
- Run the same scenerio, things work

I tried byte-compile-file "lisp/wid-edit.el" to test if a newly generated
".elc" file would work. I does not work.

The above said BUG happens only when I use a GCC compiled Emacs binary
and not with the binary generated through MSVC

I also did the following test to rule out the elisp compilation
regression:
- I built and installed Emacs using MSVC (D:/GNU/emacs-msvc)
- I built and installed Emacs using GCC in a different location
(D:/GNU/emacs-gcc)
- I launched GNU Emacs (GCC compiled binary)
- Opened the "wid-edit.el" file from the MSVC installation
- Byte compiled it
- Launched MSVC emacs and it works just fine.

I seriously doubt the Emacs binary/executable generated by MSVC and GCC

with regards,
dhruva
-- 
Dhruva Krishnamurthy
Home: http://www32.brinkster.com/schemer/

Re: other/9818 (Was: Re: Emacs - MinGW32 on W2K)

[Wolfgang Bangerth]

> A reproducible recepie for a crash:
> - Launch emacs
> - Load library "recentf" (load-library "recentf")
> - Set the recentf mode (recentf-mode t)
> - M-x recentf-open-files
> CRASH (Emacs Abort Dialog: A fatal error has occured!)

It is entirely possible that this is due to a bug in gcc. However, please 
note that it happens _somewhere_ inside Emacs, a package of several 
100,000 lines of code. Since gcc developers are not usually acquainted 
with large packages, it is standing gcc policy [1] to ask submitters to 
try to narrow down such problems. What we would need is what we call a 
self-contained testcase: one file with one or more functions where the 
miscompilation happens.

I understand that this is placing a burden on submitters of bug reports. 
However, it is virtually impossible to find a miscompilation if you don't 
know what a code does -- you just don't know what expected and wrong 
effects of functions are.

The usual procedure for reducing bugs like yours is to try compiling the 
files which you suspect might be miscompiled with a different compiler and 
see whether this helps. If you have found the one file that is 
miscompiled, try to figure out which function inside it might be the 
problem and try to successively reduce the size of the problem from
"emacs-size" to something that might fit into a few 100 lines of code at 
most.

Sorry for not being of more help,
  Wolfgang

[1] Please see http://gcc.gnu.org/bugs.html

-------------------------------------------------------------------------
Wolfgang Bangerth             email:            bangerth@ticam.utexas.edu
                              www: http://www.ticam.utexas.edu/~bangerth/

Re: Emacs - MinGW32 on W2K

[Eli Zaretskii]

> From: "Dhruva Krishnamurthy" <seagull@fastmail.fm>
> Date: Mon, 24 Feb 2003 21:17:20 +0530
> 
> A reproducible recepie for a crash:
> - Launch emacs
> - Load library "recentf" (load-library "recentf")
> - Set the recentf mode (recentf-mode t)
> - M-x recentf-open-files
> CRASH (Emacs Abort Dialog: A fatal error has occured!)

Can you run Emacs under GDB and post here the C-level and Lisp-level
backtraces at the point of the crash?

You can find some guidance for debugging Emacs in the file etc/DEBUG.
Windows-specific instructions are near the end of the file.

Feel free to ask here specific questions about how to continue
debugging given what you find with GDB.

TIA

Re: Emacs - MinGW32 on W2K

[Dhruva Krishnamurthy]

On Tue, 25 Feb 2003 20:57:58 +0200, "Eli Zaretskii" <eliz@elta.co.il>
said:
> > From: "Dhruva Krishnamurthy" <seagull@fastmail.fm>
> > Date: Mon, 24 Feb 2003 21:17:20 +0530
> > 
> > A reproducible recepie for a crash:
> > - Launch emacs
> > - Load library "recentf" (load-library "recentf")
> > - Set the recentf mode (recentf-mode t)
> > - M-x recentf-open-files
> > CRASH (Emacs Abort Dialog: A fatal error has occured!)
> 
> Can you run Emacs under GDB and post here the C-level and Lisp-level
> backtraces at the point of the crash?

This is the backtrace I have:

Program received signal SIGTRAP, Trace/breakpoint trap.
0x77fa018d in ?? ()
(gdb) bt
#0  0x77fa018d in ?? ()
#1  0x0101f9b9 in funcall_lambda (fun=1099717760, nargs=12,
    arg_vector=0x82f3c4) at eval.c:2927
#2  0x0101f45d in Ffuncall (nargs=13, args=0x82f3c0) at eval.c:2797
#3  0x010f4a91 in Fbyte_code (bytestr=830611668, vector=1101934848,
    maxdepth=14) at bytecode.c:709
#4  0x0101f9b9 in funcall_lambda (fun=1099044736, nargs=1,
arg_vector=0x82f51c)
    at eval.c:2927
#5  0x0101f45d in Ffuncall (nargs=2, args=0x82f518) at eval.c:2797
#6  0x0101f18c in call1 (fn=293984980, arg1=1367078716) at eval.c:2532
#7  0x0106792f in mapcar1 (leni=10, vals=0x0, fn=293984980,
seq=1367078556)
    at fns.c:2900
#8  0x01067c0f in Fmapc (function=293984980, sequence=1367078556) at
fns.c:2975
#9  0x0101f5c6 in Ffuncall (nargs=3, args=0x82f650) at eval.c:2743
#10 0x010f4a91 in Fbyte_code (bytestr=830611540, vector=1099770624,
maxdepth=7)
    at bytecode.c:709
#11 0x0101f9b9 in funcall_lambda (fun=1099044576, nargs=0,
arg_vector=0x82f7b4)
    at eval.c:2927
#12 0x0101f45d in Ffuncall (nargs=1, args=0x82f7b0) at eval.c:2797
#13 0x0101f133 in apply1 (fn=291898684, arg=291212292) at eval.c:2492
#14 0x010f3d07 in Fcall_interactively (function=291898684,
    record_flag=291212340, keys=1096597504) at callint.c:395
#15 0x0101208b in Fcommand_execute (cmd=291898684, record_flag=291212340,
---Type <return> to continue, or q <return> to quit---
    keys=291212292, special=291212292) at keyboard.c:9615
#16 0x01012427 in Fexecute_extended_command (prefixarg=291212292)
    at keyboard.c:9726
#17 0x0101f5ac in Ffuncall (nargs=2, args=0x82fad0) at eval.c:2740
#18 0x010f31cf in Fcall_interactively (function=291284044,
    record_flag=291212292, keys=1096597504) at callint.c:846
#19 0x0101208b in Fcommand_execute (cmd=291284044, record_flag=291212292,
    keys=291212292, special=291212292) at keyboard.c:9615
#20 0x01006e75 in command_loop_1 () at keyboard.c:1753
#21 0x0101d4f7 in internal_condition_case (bfun=0x1006b50
<command_loop_1>,
    handlers=291334676, hfun=0x10065e0 <cmd_error>) at eval.c:1351
#22 0x010068fd in command_loop_2 () at keyboard.c:1290
#23 0x0101d03f in internal_catch (tag=291286980,
    func=0x10068d0 <command_loop_2>, arg=291212292) at eval.c:1112
#24 0x010068ac in command_loop () at keyboard.c:1269
#25 0x01006370 in recursive_edit_1 () at keyboard.c:985
#26 0x010064a6 in Frecursive_edit () at keyboard.c:1041
#27 0x01003127 in main (argc=2, argv=0x9f2ca8) at emacs.c:1659
#28 0x01001170 in __mingw_CRTStartup ()
#29 0x01001013 in mainCRTStartup ()
#30 0x77e97d08 in _libwinmm_a_iname ()
(gdb)

with regards,
dhruva
-- 
Dhruva Krishnamurthy
Home: http://www32.brinkster.com/schemer/