How are symbols read during core dump analysis?

hs_linux · 07-21-2010, 04:37 AM

I am using GDB/KDevelop to analyse a coredump. When a coredump is loaded, symbols from several libraries that are related to the program are read. I think the debugger must be tracking down dependencies of the program (through something like ldd) and then reading their symbols. Please confirm. Can I get some useful documentation on internal details?
What if the crash is coming from a library that was loaded at runtime but is not specified as a dependency while building the program. Will it's symbols get read?

Thanks

foodown · 07-22-2010, 12:25 AM

http://www.dialogic.com/support/help...all/tn957.aspx
http://www.unix.com/unix-advanced-ex...-analysis.html
http://programming.itags.org/unix-li...ramming/87358/

hs_linux · 07-22-2010, 01:40 AM

Thanks for the reply foodown. I followed these links but unfortunately these explain gdb usage more or less and not what I am looking for. How does gdb come to know about libraries whose symbols are to be read?

wje_lq · 07-22-2010, 07:42 AM

Quote:

Originally Posted by hs_linux

Thanks for the reply foodown. I followed these links but unfortunately these explain gdb usage more or less and not what I am looking for. How does gdb come to know about libraries whose symbols are to be read?

The names of the files containing the object code for these libraries (and therefore containing the symbols desired) are in the object code (the ELF file) which you are running. Try doing this to the file containing some program you have compiled and linked:

Code:

readelf program_of_interest | less

hs_linux · 07-28-2010, 08:29 AM

Thanks for the reply wje_lq. readelf provides some useful information. I work on JNI. Part of my application is Java and partly C/C++. During Core dump analysis, I only mention path to Java which doesn't contain reference to my application's C++ libraries/files. I guess the core dump would be containing information here about these dependant C++ libraries.

Thanks.