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From: Christian Biesinger <cbiesinger@google.com>
Date: Thu, 29 Oct 2020 13:29:51 +0100
Message-ID: <CAPTJ0XFkJJ=hPwzfN6LKeL-xGOuHJDkeq8cfSL2hxy3GOXHvEA@mail.gmail.com>
Subject: Re: [Question] Is there a way to specify an offset to the loaded
 symbols?
To: Marten Ringwelski <git@maringuu.de>
Cc: Reuben Thomas via Gdb <gdb@sourceware.org>
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On Thu, Oct 29, 2020 at 9:23 AM Marten Ringwelski <git@maringuu.de> wrote:
>
> Hello,
> for some reason that is not important here I need to debug a binary that is executed by calling the linker manually.
> In my case I do `/lib/ld-musl-x86_64.so.1 binary`.
> The problem with this is that gdb now obviously thinks that I want to debug `/lib/ld-musl-x86_64.so.1`. This is not the case.
> Loading the symbols from `binary` does not help since the the linker loads the process into memory and the jumps to its main.
>
> In other words I have the symbols for the binary to be debugged but the binary is loaded into memory with an offset so the symbols are offseted.
> Is there any way to get this working?

add-symbol-file lets you specify an address but maybe it's easier if
you just use patchelf --set-interpreter to make it use
/lib/ld-musl-x86_64.so.1

Christian