Re: Anyone working on ftrace function graph support on ARM?

Tim Bird
2009-03-25T18:38:56Z

Russell King - ARM Linux wrote:
> On Wed, Mar 25, 2009 at 06:05:33PM +0100, Uwe Kleine-K�nig wrote:
>> On Wed, Mar 25, 2009 at 09:34:07AM -0700, Tim Bird wrote:
>>> Russell King - ARM Linux wrote:
>>>> As pointed out in my previous mail, identifying where on the stack the
>>>> return address is stored is only possible for OABI with frame pointers.
>>>>
>>>> EABI will probably be possible with the stack unwinding code, but it
>>>> probably won't be cheap. The EABI unwinder is scheduled for merging
>>>> during the present now-open merge window.
>> EABI with frame pointers should work, too, shouldn't it?
>
> Yes, as I said at the top of my reply dated Wed, 25 Mar 2009 09:57:51 +0000

It turns out you can't use -pg and -fomit-frame-pointers at the same time.
At least, my gcc complains about this:
$ make
arm-sony-linux-gnueabi-dev-gcc -g -pg -fomit-frame-pointer -o hello hello.c
arm-sony-linux-gnueabi-dev-gcc: -pg and -fomit-frame-pointer are incompatible
make: *** [hello] Error 1

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Tim Bird
Architecture Group Chair, CE Linux Forum
Senior Staff Engineer, Sony Corporation of America
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