Re: [Libmesh-devel] Still Really Dislike Automake

[Jed B. <je...@je...>]

Roy Stogner <roy...@ic...> writes:

> On Thu, 30 Aug 2018, Paul T. Bauman wrote:
>
>> I would love to see how it could be sped up. The vast majority of
>> time in make install is spent in linking the library and there's no
>> getting around that.
>
> Looping over directory after directory costs some time, and I've heard
> a non-recursive automake setup would fix that.

It also parallelizes better because make has a flat and complete
dependency graph.  Non-recursive make is much better.

> For linking the library, IIRC most modern linkers operate in serial
> unless you explicitly try to tell them to parallelize?  That's
> annoying and we could look into that if it bothers people.
>
> I think Derek specifically referred to the re-linking of apps whenever
> the library changes, though.  That's definitely more paranoid than it
> needs to be.  

It's necessary to catch errors if a symbol is removed from the library.
Automake/make has no way to know if changes have that effect.

It is possible to link a bunch of examples together into one executable
that behaves differently depending on its name (for example).