Make ordering (Re: namespace / typing thrash ...)

[Lubos Lunak]

On Monday 16 of April 2012, Matúš Kukan wrote:
> On 16 April 2012 18:23, Lubos Lunak <l.lunak at suse.cz> wrote:
> >  It is made even worse by the fact that make+gbuild order build commands
> > so that allmost all compiles go first and linking goes last
>
> As I've seen complaining about this, I was thinking..
> Now, when sw links against svx, make starts compiling sw's sources
> after header files related to svx are in solver. (Because sw most
> probably includes them.)
> We can change that so sw would also wait on library svx. and only then
> start building.
> I am not sure how much would that hurt parallelism but maybe not that
> much and it could be improvement in the sense of ordering?

 I don't think it would hurt parallelism much, because the linking of svx 
needs to be done somewhen, and make should have enough of other stuff to do. 
On the other hand, I doubt such one change would change much. Could gbuild be 
changed so that each library target depends on its dependent libraries not 
only for linking, but also for compiling its sources? That would essentially 
change it to be like recursive make, but without the disadvantages (that's 
how cmake builds in practice, and there seems to be always enough to 
compile).

 Other option I've been thinking of is simply patching our make to be smarter 
about selecting the next target to build.

-- 
 Lubos Lunak
 l.lunak at suse.cz