Re: Compiling x86 with and without frame pointer

[David Zaffiro]

> I looked at 2.5.47 (with a splattering of performance patches) using 
> gcc 2.95.4 (Debian Woody), on a 16-way NUMA-Q, and did some kernel
> compile testing. The times to do the tests were almost identical
> (within error noise), but the kernel was indeed smaller
> 
>    text    data     bss     dec     hex filename
> 1873293  396231  459388 2728912  29a3d0 2.5.47-mjb1/vmlinux
> 1427355  396875  455356 2279586  22c8a2 2.5.47-mjb1-frameptr/vmlinux
> 

I can't think of any reason why the data- and bss-part of the kernel are 
influenced by a framepointer option, this seems highly illogical. It 
shouldn't make any difference as far as I can tell, maybe you altered 
other options as well? (Could be strange compilerbehaviour though)

Keith's results seem more reliable:

# size 2.4.20-rc2-*/vmlinux
    text    data     bss     dec     hex filename
2669584  337972  402697 3410253  34094d 2.4.20-rc2-fp/vmlinux
2676919  337972  402697 3417588  3425f4 2.4.20-rc2-nofp/vmlinux