Re: [REGRESSION] Recent change to kernel spikes out ccache/distcc

[David Miller <davem@davemloft.net>]

From: "Theodore Ts'o" <tytso@mit.edu>
Date: Tue, 06 Jan 2009 10:15:26 -0500

> The following commit, ad7a953c, "kbuild: strip generated symbols from
> *.ko" which was merged to the mainline last week (December 28th) has the
> unfortunate side effct of making ccache useless.  That's because all
> files are now built using a two step process.  First they are compiled
> to assembly via "gcc -S -o .tmp_foo.s" and then assembled via "gcc" in a
> separate step.  Unfortunately, ccache doesn't seem to be able to cache
> either the compilation or the assembly step (and it may not be worth it
> once the two steps are separated).

I think the problem might be that the assembler source always
"changes" because a different date or timestamp string is put in there
by gcc every time the assembler source is built.