JehanneOS/newlib
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

add more words

Browse Source
This commit is contained in:
Christopher Faylor 2002-01-30 02:44:21 +00:00
parent 1c2b9fe563
commit 8e2deb48d6
1 changed files with 68 additions and 61 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
winsup/cygwin/how-to-debug-cygwin.txt
View File

@ -1,22 +1,25 @@
Copyright 2001 Red Hat Inc., Egor Duda
So, your favorite program has crashed? And did you say something about
'stackdump'? Or it just prints its output from left to right and upside-down?
Well, you can file an angry bug report and wait until some of the core
developers try to reproduce your problem, try to find what's the matter
with your program and cygwin and fix the bug, if any. But you can do something
better than that. You can debug the problem yourself, and even if you can't
fix it, your analysis may be very helpful. Here's the (incomplete) howto on
cygwin debugging.
'stackdump'? Or it just prints its output from left to right and
upside-down? Well, you can file an angry bug report and wait until some
of the core developers try to reproduce your problem, try to find what's
the matter with your program and cygwin and fix the bug, if any. But
you can do something better than that. You can debug the problem
yourself, and even if you can't fix it, your analysis may be very
helpful. Here's the (incomplete) howto on cygwin debugging.
1. The first thing you'll need to do is to build cygwin1.dll and your crashed
application from sources. To debug them you'll need debug information, which
is normally stripped from executables.
1. The first thing you'll need to do is to build cygwin1.dll and your
crashed application from sources. To debug them you'll need debug
information, which is normally stripped from executables. You probably
also want to build a version of the dll with more debugging capabilities
by reconfiguring your build directory, specifying the --enable-debugging
option to configure.
2. Create known-working cygwin debugging environment.
- create a separate directory, say, c:\cygdeb, and put known-working
- create a separate directory, say, c:\cygdeb, and put known-working
cygwin1.dll and gdb.exe in it.
- create a wrapper c:\cygdeb\debug_wrapper.cmd:
- create a wrapper c:\cygdeb\debug_wrapper.cmd:
========= debug_wrapper.cmd =========
rem setting CYGWIN_TESTING environment variable makes cygwin application
@ -26,7 +29,7 @@ c:\cygdeb\gdb.exe -nw %1 %2
===================================
3. Try to use cygwin's JIT debugging facility:
- add 'error_start=c:\cygdeb\debug_wrapper.cmd' to CYGWIN environment
add 'error_start=c:\cygdeb\debug_wrapper.cmd' to CYGWIN environment
variable. When some application encounters critical error, cygwin will stop
it and execute debug_wrapper.cmd, which will run gdb and make it to attach to
the crashed application.
@ -42,6 +45,10 @@ c:\cygdeb\gdb.exe -nw %1 %2
timeouts introduced by strace, and -m option allows you to mask certain
classes of *_printf() functions, reducing timeouts even more.
Note that strace does not use the cygwin DLL and so any process that it
starts does not inherit a cygwin environment. It is equivalent to starting
a program from the command prompt.
5. Problems at early startup.
Sometimes, something crashes at the very early stages of application
initialization, when JIT debugging facility is not yet active. Ok, there's