[Bug middle-end/8743] receiving result from __builtin_return_address() beyond stack top causes segfault

[normbograham at yahoo dot com]

------- Additional Comments From normbograham at yahoo dot com  2005-09-08 01:43 -------
Ed: 
I also have the same problem, but a little thought gives you a good work-
around.   First a little background.   There is a function that calls main.  
This is the last function on the stack you can query using 
__builtin_return_address.  If you query who calls that function you get a 
seg "fault" , quicker then grass through a goose.   They should have called 
their __builtin_return_address(0) logic from there and stored the address, 
stopping future calls to this function from going further.    This is exactly 
what you can do from main.  (This is your workaround) Call 
_builtin_return_address(0) from main, store the result to a global, and you 
can compare against this address in the future (provided your not in an 
at_exit, or on_exit function call stack).  Of course you've got to turn 
optimization off (-O0), I think or the results could be silly.   Then you can 
query back to the main function (or one up if you wish to the boot-up 
routine.).  Again: Dont be silly, turn off optmization (or function calls will 
colapse), store the result from main, and DONT call from "onexit" or "atexit" 
routines.

good luck.
n.

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=8743