GDB remote debugging stub: Question about memory read

Niklas Quarfot Nielsen
Mon Sep 27 09:20:00 GMT 2010

That worked! Thank you so much - you saved my day. (Probably a couple of days to be more exact).



On Sep 27, 2010, at 11:16 , Pedro Alves wrote:

> On Monday 27 September 2010 09:54:04, Niklas Quarfot Nielsen wrote:
>> GDB tries to read 0x40 bytes starting at address 0xffffffff6effffc0, which (I guess) is from the RSP.
>> Packet: mffffffff6effffc0,40
>> My question is:
>> Why does GDB try to read 0x40 bytes, when there is only 0x20 bytes on the stack (RBP-RSP)?
>> The architecture is an AMD64 and the version of GDB is 7.1(x86_64-gnu-linux).
>> I appreciate any answer and/or clue to why GDB behaves like this.
>> I have tried to look through the remote debugging source code of GDB, but this has not given me any answers.
>> If needed, I can post debugging information from the target code in GDB.
> 0x40 bytes is GDB's stack cache line size (dcache.c).
> Try "(gdb) set stack-cache off".
> -- 
> Pedro Alves

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