How Can I Accurately Debug Core Files Generated on Different Linux Distributions?

Debugging Core Files Across Different Linux Distributions

When a core file is generated on a Linux distribution different from your development environment, the stack trace may not be entirely meaningful. Dynamically linked executables rely on addresses within shared libraries, and these addresses can vary between distributions. GDB may incorrectly attribute the crash to functions in your copy of the library, whereas the customer's system might have a different function at the same address.

To validate the accuracy of the stack trace, disassembling the function in question may reveal that the address falls within an instruction or is preceded by a non-CALL instruction. In such cases, the stack trace is unreliable.

To obtain a more accurate trace, you can request the customer to provide the following libraries used by the problematic binary:

cd /
tar cvzf to-you.tar.gz lib/libc.so.6 lib/ld-linux.so.2 ...

On your system:

mkdir /tmp/from-customer
tar xzf to-you.tar.gz -C /tmp/from-customer
gdb /path/to/binary
(gdb) set solib-absolute-prefix /tmp/from-customer
(gdb) core core  # Important: Set solib-... before loading core
(gdb) where      # Get meaningful stack trace!

Debugging with Optimized Binaries

Instead of advising customers to run a -g binary, a preferred approach is to build the binary with both -g and -O2 optimization flags and strip the debug information before distribution:

build with -g -O2 -o myexe.dbg
strip -g myexe.dbg -o myexe
distribute myexe to customers
when a customer gets a core, use myexe.dbg to debug it

This allows for full symbolic debugging (file/line, local variables) without sharing sensitive source code details.

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