Re: [Bug-zile] Problems with parallel build

[Gary V. Vaughan]

Hi Reuben,

On 9 Jul 2012, at 07:56, Reuben Thomas wrote:
> There's a problem when running:
> 
> make maintainer-clean && ./bootstrap && ./configure && make
> "DISTCHECK_CONFIGURE_FLAGS=--enable-valgrind" check
> 
> although I still haven't got to the bottom of why it ends up doing two
> parallel builds.

Surprising! I run `make -j2' as a matter of habit, and haven't experienced
any issues at all!

At first I thought it might be because you were running `make check' rather
than `make all check', and that the Zile Makefile.am's were missing some of
the dependencies between the check rule, and the (in your tests) implicit
run of the make all rules...

But, adding back the missing `all' doesn't make any noticable difference.
Upon further investigation, I can only reproduce this problem when I
introduce the `-l 4.0' flag, which I never use personally.  If things start
working for you too when you remove that flag, then it seems like we've
found gmake bug.

> However, I was led to another oddity: why is "." in SUBDIRS in the
> top-level Makefile.am?

No, that's correct.  By default Automake generates rules that build the
current directory before descending into subdirs, unless you explicity name
the current directory with a `.' in SUBDIRS.  We definitely need to run the
gnulib part of the build before we can begin the rest of Zile's non-recursive
build, hence:

  SUBDIRS = lib .

Cheers,
-- 
Gary V. Vaughan (gary AT gnu DOT org)