Re: stack overflow on Sparc64

[Mikulas Patocka <mpatocka@redhat.com>]

On Fri, 20 Jun 2008, David Miller wrote:

> From: Mikulas Patocka <mpatocka@redhat.com>
> Date: Fri, 20 Jun 2008 18:22:33 -0400 (EDT)
>
>> On Fri, 20 Jun 2008, David Miller wrote:
>>
>>> From: David Miller <davem@davemloft.net>
>>> Date: Fri, 20 Jun 2008 14:44:24 -0700 (PDT)
>>>
>>>> I agree on both counts.  Although I'm curious what the average stack
>>>> frame sizes look like on x86_64 and i386, and also how this area
>>>> appears on powerpc.
>>>
>>> I also one to mention in passing that another thing we can do to
>>> help deep call stack sizes is to make call chains more tail-call
>>> friendly when possible.
>>
>> ... and remove -fno-optimize-sibling-calls?:
>>
>> Makefile:
>> ifdef CONFIG_FRAME_POINTER
>> KBUILD_CFLAGS   += -fno-omit-frame-pointer -fno-optimize-sibling-calls
>> else
>> KBUILD_CFLAGS   += -fomit-frame-pointer
>> endif
>>
>> --- maybe it could be better to remove it, instead of some inlining that I
>> made. Or do you see a situation when for debugging purpose, user would
>> want -fno-optimize-sibling-calls?
>
> Yes for debugging and other things it has to stay.

If you want it to stay, then it doesn't make sense to make functions 
tail-call-friendly --- because it should not crash with or without 
debugging.

Mikulas