__builtin_return_address()
H . J . Lu
hjl@lucon.org
Mon Jul 23 11:17:00 GMT 2001
On Mon, Jul 23, 2001 at 11:13:54AM -0700, Richard Henderson wrote:
> On Mon, Jul 23, 2001 at 10:29:49AM -0700, H . J . Lu wrote:
> > * doc/extend.texi: Update __builtin_return_address and
> > __builtin_frame_address.
>
> Ok.
>
> > +randome value. In addition, @code{__builtin_frame_address} may be used
>
> "random"
>
Here is the new patch. I will check it in today.
Thanks.
H.J.
---
2001-07-23 H.J. Lu (hjl@gnu.org)
* doc/extend.texi: Update __builtin_return_address and
__builtin_frame_address.
--- gcc/doc/extend.texi.stack Tue Jul 17 08:23:30 2001
+++ gcc/doc/extend.texi Mon Jul 23 10:28:20 2001
@@ -3703,7 +3703,9 @@ The @var{level} argument must be a const
On some machines it may be impossible to determine the return address of
any function other than the current one; in such cases, or when the top
-of the stack has been reached, this function will return @code{0}.
+of the stack has been reached, this function will return @code{0} or a
+random value. In addition, @code{__builtin_frame_address} may be used
+to determine if the top of the stack has been reached.
This function should only be used with a non-zero argument for debugging
purposes.
@@ -3725,8 +3727,13 @@ has a dedicated frame pointer register,
then @code{__builtin_frame_address} will return the value of the frame
pointer register.
-The caveats that apply to @code{__builtin_return_address} apply to this
-function as well.
+On some machines it may be impossible to determine the frame address of
+any function other than the current one; in such cases, or when the top
+of the stack has been reached, this function will return @code{0} if
+the first frame pointer is properly initialized by the startup code.
+
+This function should only be used with a non-zero argument for debugging
+purposes.
@end deftypefn
@node Other Builtins
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