How does GDB get the function call stack

[hilbert]

 @Andrew Dinn 

Now I totally understand. Thank you very much for your patience.
By the way, when a multithreaded program hits a breakpoint, GDB can use the command: thread ID 
 to switch between threads arbitrarily,  and view the memory and other information of each thread. 
This is also implemented using ptrace, right?















At 2022-08-16 17:33:07, "Andrew Dinn" <adinn@redhat.com> wrote:
>On 16/08/2022 10:19, hilbert via Gdb wrote:

>When it says without debug information I believe that means without 
>DWARF info. This info is located either in .debug_xxx sections embedded 
>in the binary or, alternatively, supplied in a separate dwinfo/dwz file 
>that is tied to the binary (e.g. by search path and file name or by a 
>build id).
>
>DWARF .debug_frame info can specify a lot more than how to do a stack 
>unwind. So, while the other methods enable this specific operation they 
>do not enable many other useful actions that gdb might need to establish 
>frame context and which DWARF info may enable. For full details see the 
>DWARF standard(s).
>
>regards,
>
>
>Andrew Dinn
>-----------
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