Re: Access to Program Counter in C

[Brian Raiter <breadbox@muppetlabs.com>]

> A M wrote:
>> Does anybody know how to access the address of the
>> current executing instruction in C while the program
>> is executing?
> doing exactly as your words say, won't be possible (as
> far as my limited experience with ix86 architecture goes),
> but something nearabout can be achieved with little inline
> assembly fragment.

Actually, there's a gcc-specific extension that can do this, namely
the unary && operator, which will return the address of a goto label:

int somefunction(void)
{
    /* ... */
    void *pc = &&here;
  here:
    /* ... */
}

Of course you shouldn't use this unless you completely don't care
about portability.

b