Is this a memory address?

I a开发者_运维百科m learning gdb, and I got my first error. This was the error:

0x00007fff83074096 in __kill ()

Is the address:

0x00007fff83074096

... a memory address in Hex format? I've converted it to decimal, out of interest, and the number is huge. I fail to believe that so many memory addresses exist.

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If you are running on a 64-bit platform, then yes, addresses that large exist. (See also: http://en.wikipedia.org/wiki/Virtual_address.)

Of course, it's possible that you simply have a buffer overflow somewhere, which has corrupted your stack, and overwritten the address with nonsense.

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Yup. It is.

It is an address in a 64 bit process's virtual memory space.

Not all of the addresses are in use (that's what an address is: it is a label only).

You can see more about the address by doing

:break 0x00007fff83074096
:list 0x00007fff83074096
:disassemble 0x00007fff83074096

See the whole of the stack bactkrace

 :bt full

In all threads

 :thread apply all bt full

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Yes, it is a memory address. Due to paging, there are vastly more memory addresses available than actual memory to back the virtual address space.

You might find running pmap -x 1 or pmap -x $$ instructive, along with looking at /proc/pid/maps contents for different processes. (cat /proc/self/maps is easy to run.)

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16 hex digits x 4 (bits represented by one hex digit) = 64 bits. You're using a 64 bit platform, why are you surprised?