Re: Any way to get rid of -MP parameter to gcc for dependency creation?

[Miles Bader]

On Fri, Jan 7, 2011 at 8:34 AM, Xan Lopez <address@hidden> wrote:
>> Do they actually do the same thing?
>
> Yes, we all build WebKit + the some testing tools. The set of files we
> build is not identical, since it changes by port, but the difference
> is negligible since most of the files are platform-independent. Of
> course perhaps we have written our stuff extremely poorly and they
> haven't, but since I have written part of ours I'm not the best person
> to comment on that (from the kind of things we need to do to improve
> it it does not seem to be the case, though).

What I meant was, do they all do the same thing _in detail_ -- for
instance, if one tracks system header dependencies and the other
doesn't, then the latter will most likely be faster, but will have
"reduced functionality."  [Your investigation into the effects of -MP
point out one such "detail" area where build tools may well differ.]
If one tool is faster than another, one should of course weight that
against the differences in functionality.

Ralf mentioned that some of the inefficiency came from build rules
intended to do automatic Makefile regeneration; do the other tools do
that?

Also, some of the inefficiencies in automake-generated Makefiles comes
from the attempt to be very portable, both in the set of tools
required to do a build (only make, sed, sh, etc, vs the requirement
for specific specialized tools to be installed for just building), the
versions of those tools (e.g. any vaguely standard make vs GNU make
only).  If another tool has additional requirements for building, that
also is a factor to be weighed against speed.

-Miles

-- 
Cat is power.  Cat is peace.