Re: [Valgrind-users] valgrind - segmentation fault on rh9

[Hong C. <hc...@N-...>]

I fixed this by rebuilding the applcation with debug option ( -g ), and
it works now.( One of the libs doesn't contain debug info before ).  As
you said , the problem is caused by uninitialized variable,
                                                                                                 
following is the detailed messages when the app is running :
==4193== Conditional jump or move depends on uninitialised value(s)
==4193==    at 0x403AD7AC: __wcslen (in /lib/libc-2.3.2.so)
==4193==    by 0x403AEA0E: __wcsrtombs (in /lib/libc-2.3.2.so)
==4193==    by 0x40377136: _IO_vfprintf_internal (in /lib/libc-2.3.2.so)
==4193==    by 0x403974B3: _IO_vsnprintf (in /lib/libc-2.3.2.so)
==4193==
==4193== Conditional jump or move depends on uninitialised value(s)
==4193==    at 0x40348829: internal_ascii_loop (in /lib/libc-2.3.2.so)
==4193==    by 0x40347084: __gconv_transform_internal_ascii (in
/lib/libc-2.3.2.so)
==4193==    by 0x403AEAC9: __wcsrtombs (in /lib/libc-2.3.2.so)
==4193==    by 0x40377136: _IO_vfprintf_internal (in /lib/libc-2.3.2.so)
==4193==
==4193== Conditional jump or move depends on uninitialised value(s)
==4193==    at 0x403AEFEE: __wcsnlen (in /lib/libc-2.3.2.so)
==4193==    by 0x403AE94A: __wcsrtombs (in /lib/libc-2.3.2.so)
==4193==    by 0x403771BC: _IO_vfprintf_internal (in /lib/libc-2.3.2.so)
==4193==    by 0x403974B3: _IO_vsnprintf (in /lib/libc-2.3.2.so)
==4193==
==4193== Conditional jump or move depends on uninitialised value(s)
==4193==    at 0x40348829: internal_ascii_loop (in /lib/libc-2.3.2.so)
==4193==    by 0x40347084: __gconv_transform_internal_ascii (in
/lib/libc-2.3.2.so)
==4193==    by 0x403AE9A8: __wcsrtombs (in /lib/libc-2.3.2.so)
==4193==    by 0x403771BC: _IO_vfprintf_internal (in
/lib/libc-2.3.2.so)                                                                                                 
 As this comes from the libc, perhaps it's not a bug of valgrind.
                                                                                                 
thanks for your help
hong



On Tue, 2003-05-27 at 12:09, Nicholas Nethercote wrote:
> On 27 May 2003, Hong Chen wrote:
> 
> > I'm using valgrind to detect leaks in my program without any luck. When
> > I  start valgrind :
> > valgrind -v myapp args
> >
> > it worked fine at the very beginning, but when it tried to load a shared
> > object , following error messages showed up :
> >
> > ==2684== Jump to the invalid address stated on the next line
> > ==2684==    at 0x0: ???
> > ==2684==    Address 0x0 is not stack'd, malloc'd or free'd
> > Segmentation fault
> >
> > Without valgrind, I haven't get any trouble to run myapp. Could anyone
> > give me a pointer ? any input would be appreciated.
> 
> That's the message you have a variable that is uninitialised, and then you
> try to jump to the "address" stored in that variable.  But since your
> program works fine normally, I'd guess it's a Valgrind bug.  Can you
> provide the full output from running with -v?  Better still, can you trim
> down your program into a small example that triggers the error?
> 
> Thanks.
> 
> N