Re: [Qemu-devel] [PATCH] build: Use separate makefile for "trace/"

[Lluís Vilanova]

Paolo Bonzini writes:

> Il 14/12/2012 14:46, Lluís Vilanova ha scritto:
>>>> The thing I like about automake is that it provides a clear set of vars to
>>>> manage the per-dir builds, thanks to using a per-dir $(MAKE); but I'm
>>>> not sure how the per-target build would be managed (except by having a
>>>> separate configure+make for each of them).
>>>> Yes, that would be it.
>> 
>> I'd certainly love to see something along those lines for the sake of 
>> makefile
>> simplicity.

> QEMU is complex enough that I'm not really sure what Automake would buy.

I'm just talking about having a build system (automake or not) that uses some
"standard" set of vars to establish what to do, plus per-directory make to
simplify management of per-directory vars (if ever needed).


>>> > Even an autoconf conversion probably would have to use separate configure
>>> > scripts for the global project and for each target.
>> If you're willing to pay for a complete recompilation for each target you can
>> just have a single configure file.

> That's not the problem.  The problem is that Autoconf does not lend well
> to the style of the QEMU build system, with many subparts that are
> enabled/disabled at configure time.

Well, for that you have conditional compilation. The linux style (obj-y) is
easier to understand, but AFAIR automake provided broader features.


>> Ah, I know that one in gcc 
>> 
>> -Wl,--whole-archive foo.a -Wl,--no-whole-archive

> Really in ld (that's what -Wl does) and not very portable...

I know, but I had no idea about the portability issues.


Again, don't take it as an intent to start some autotools flame, I was just
curious :)


Lluis

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