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Date: Mon, 12 Mar 2012 12:01:28 -0400
From: Ryan Johnson <ryan DOT johnson AT cs DOT utoronto DOT ca>
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To: Michel Bardiaux <MBardiaux AT mediaxim DOT be>,
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Subject: Re: Unfolding the stack
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On 12/03/2012 11:20 AM, Michel Bardiaux wrote:
>> Alternatively, you could compile with -g and try to traverse the debug
> info tables gdb uses to work>  around everything nasty gcc does, but
> there's no clean API there that I know of.
>
> Since cygwin_stackdump does not dare to tread there...
Pretty much. I would just note that this is not cygwin-specific. Nobody 
but gdb dares as far as I know.

>> Out of curiosity, what is your library currently using to generate backtraces?
>>
>> Well you just snipped it: pipe/fork/dup to catch the stderr of cygwin_stackdump called in the forked process.
I meant in the original, non-ported version of the library which you are 
porting to cygwin. Presumably it did not call cygwin_stackdump.

>> There's a backtrace facility in glibc (man backtrace), but it's got a long list of caveats as well, including death by -fomit-frame-pointer (it doesn't use any debug/unwind info emitted by the compiler).
> In what package? I have cygwin basics + gcc installed, and no backtrace in any .h.
This was in the context of my previous question (see above). Cygwin uses 
newlib, not glibc.

Ryan


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