Re: [Axiom-developer] Building Axiom twice

[Waldek Hebisch]

Gabriel Dos Reis wrote:
> Waldek Hebisch <address@hidden> writes:
> 
> | In the main Makefile we have:
> | 
> | SUBDIRS = src/lib lsp src
> | 
> | and the recursive part will build subdirectories in this strictly
> | sequential order.
> 
> No, that is untrue if you say "make -jN", aka parallel build, which
> build-improvements must support.
> 
> |  So, as long as recursive logic remains sequential
> | stamps are redundant.
> 
> I think you're making too much of oversimplifying unspoken assumptions.
> README.build-improvements reads:
> 
>    ...
>    * Support parallel build.
>      Notice that GCL does not support parallel build.  So we can punt
>      on build of GCL.  We should work with Camm to fix GCL build
>      upstream.
>    ...
> 
> 
> If you remove the dependency, you break parallel builds.
> (Currently, you can do parallel builds until you hit algebra --
> assumign you don't have to build GCL).
> 

Have you tried to do parallel builds?  I tried, but it failed in boot
directory. FYI I changed lsp Makefile to pass '-j 1' to GCL because ATM
on my dual core machines build fails using system GCL (it works using
bundled GCL, also system GCL on single core machines works fine). 

My impression is that you will loose most opportunities for
parallelism: recursive logic is seqential and dependence via stamps
means that one subdirectory must finish before another starts. 
If you make dependency on stamp effective how do you want to
avoid starting two makes (in paralel) in src subdirectory -- make
logic will not prevent this. So, I think that to trurly support paralel
builds you need a single Makefile.

--
                              Waldek Hebisch
address@hidden