Minidump symbols module id and Build id from ELF on Linux

Question

I'm generating symbols file for an executable for minidump. The first line in the minidump symbols file contains specific id of the executable for which the file was generated. How can I find that id inside the executable? When I use readelf to check build id then it's something different (even the length is different).

Answer 1

How can I find that id inside the executable?

Which is that id? Presumably the one your tool uses, except you didn't tell us which tool you actually use.

Most Linux tools (such as GDB) use a special NT_GNU_BUILD_ID note in the elf binary to associate debug info with the binary. You can see that build-id in readelf -n a.out output.

When I use readelf to check build id then it's something different

Again, what exactly do you see? What command do you run?

Maybe they are one and same, and you are just "holding it wrong". Or they are encoded differently, or you are looking at the wrong thing. We can't tell.