[cairo] Rethinking cairo's build system

[Michael Sweet]

Nguyễn Thái Ngọc Duy wrote:
> On 6/19/06, Carl Worth <cworth at cworth.org> wrote:
>> On Fri, 16 Jun 2006 18:07:07 -0700, "Vladimir Vukicevic" wrote:
>> >
>> > > 2) Whenever configure is run, every source file is rebuilt
>> >
>> > True, but how often do you re-run configure?
>>
>> "A lot". I haven't spent a lot of time looking into all the causes,
>> but every time I've spent time with "git bisect" it seems I always
>> rebuilding everything even when I know only a few files have changed.
> You should use ccache in those cases.

FWIW, I've found that ccache often leads to substantially slower
compiles when many files are affected by a change and actually
require a recompile.  The difference was so great (up to 2 times
slower on my build systems) that I no longer use it...

The issue seemed to be one of IO speed - copying .o files can be
very expensive on systems with slow disks or file-systems that don't
support hard links.

Not to knock Andrew's otherwise excellent ccache program - just want
to point out that ccache is not a fix for broken dependencies, and
when you *do* need to recompile the overhead is a lot higher on
slower systems...

-- 
______________________________________________________________________
Michael Sweet, Easy Software Products           mike at easysw dot com
Internet Printing and Document Software          http://www.easysw.com