Linus Torvalds <torvalds <at> osdl.org> wrote:
>
> 
> 
> On Mon, 31 Oct 2005, Andrew Morton wrote:
> > 
> > Are you sure these kernels are feature-equivalent?
> 
> They may not be feature-equivalent in reality, but it's hard to generate 
> something that has the features (or lack there-of) of old kernels these 
> days. Which is problematic.

Probably.

> But some of it is likely also compilers. gcc does insane padding in many 
> cases these days. 

2.6.14 `make allnoconfig':

gcc-2.95.4:

	bix:/usr/src/25> size vmlinux 
	   text    data     bss     dec     hex filename
	 665502  152379   55120  873001   d5229 vmlinux

gcc version 4.1.0 20050513 (experimental):

	bix:/usr/src/25> size vmlinux
	   text    data     bss     dec     hex filename
	 761415  151851   55280  968546   ec762 vmlinux

(There's a new reason for retaining gcc-2.95.x support)

(gcc-4.x can probably be tuned up with appropriate `-malign' options)

> And a lot of it is us just being bloated. Argh.

2.5.71, gcc-2.95.4:

	bix:/usr/src/aa/linux-2.5.71> size vmlinux 
	   text    data     bss     dec     hex filename
	 501892   54163   40420  596475   919fb vmlinux

yes, it got bigger.   .data went through the roof - maybe inlined debug stuff?

2.6.8.1, gcc-2.95.4:

	bix:/usr/src/aa/linux-2.6.8.1> size vmlinux
	   text    data     bss     dec     hex filename
	 605032  153817   58176  817025   c7781 vmlinux

It happened somewhere between 2.5.71 and 2.6.8.

2.4.x doesn't have allnoconfig, so no numbers for that.