+2001-07-23 H.J. Lu (hjl@gnu.org)
+
+ * doc/extend.texi: Update __builtin_return_address and
+ __builtin_frame_address.
+
2001-07-23 Richard Henderson <rth@redhat.com>
* config/i386/i386.c (ix86_expand_setcc): Don't use method 0
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.
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