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Re: __builtin_return_address
> Date: Thu, 2 Nov 2000 00:19:47 -0800
> From: "Zack Weinberg" <zackw@Stanford.EDU>
>
> You're missing the point here. Yes, on x86/linux without
> -fomit-frame-pointer, __builtin_return_address(N) for N>0 is more
> likely to work than on some other platforms. It still isn't
> guaranteed. It might return zero back when there's still stack
> frames, skip over active frames, surprise you with frames you didn't
> expect, or crash instead of returning 0 when you run out of frames.
> And I wouldn't be too shocked if it made demons fly out of my nose,
> either.
All I've said originally was that the current GCC docs does not say
anything about undefined/unguaranteed behavior, and neither does it
mention demons flying out of your nose. It says that
__builtin_return_address either returns a valid address, or, if it
can't get a valid address, it returns zero.
Therefore, I suggested to amend the docs.
Now, what point does this observation miss?