Patch for Cross-Reference Phandles

[Eitan Adler]

On Sat, Sep 14, 2013 at 8:06 PM, Adrian Chadd <adrian at freebsd.org> wrote:
> On 14 September 2013 17:04, Eitan Adler <lists at eitanadler.com> wrote:
>
>>
>> With an explicit zeroing:
>>
>>    text    data     bss     dec     hex filename
>>    1572     484      16 2072     818 a.out
>>
>> Without:
>>
>>    text    data     bss     dec     hex filename
>>    1572     484      16 2072     818 a.out
>
>
> This is exactly the opposite of what I see with kernel code though. Eg,
> kern_umtx.c and it's very large up-front allocated array. Same as the
> upfront array of KTR entries for early boot tracing.
>
> Try bumping it to something stupid like 65536 and retest?
>
> Is this a gcc-4.2 versus clang difference?

#ifdef EXPLICIT
        int foo[65536] = { 0 };
#else
        int foo[65536];
#endif

int main()
{
        int i;
        for (i = 0; i < 2; i++) {
                foo[i] = i;
        }
}



No optimizations.

   text    data     bss     dec     hex filename
   1572     484  262152  264208   40810 clang-explicit
   1572     484  262160  264216   40818 clang-implicit

   1508     456  262184  264148   407d4 gcc46-explicit
   1508     456  262176  264140   407cc gcc46-implicit

   1652     456  262184  264292   40864 gcc49-explicit
   1652     456  262176  264284   4085c gcc49-implicit


I'm not sure of the cause of the 8 byte difference.



-- 
Eitan Adler