Re: unesthetic build commands generated by automake

[Bruno Haible]

Alexandre Duret-Lutz writes:

>  Bruno> `test -f 'hello.c' || echo './'`hello.c
> 
> More info on this topic here:
> http://sources.redhat.com/ml/automake/2002-01/msg00144.html

Thanks I didn't know this is a recurrent theme...

> To summarize:
>   - people agree this command seems to make no sense for suffix rules
>   - it's useful only for non-suffix rules (when using per-target flags
>     or subdir objects).
>   - still, it was added to fix an issue related to _suffix_ rules
>   - but this issue wasn't explained on the mailing list, and the
>     patch submitter doesn't recall what it was

The issue being VPATH support for non-GNU makes, my summary is that
they don't support VPATH well:

   1) GNU make supports VPATH with both .c.o and %.o:%.c rules.

   2) Solaris make should not be used with VPATH at all, as it randomly
      changes Makefile variables.

   3) FreeBSD make does not support %.o:%.c rules at all. For the
      remaining .c.o rules VPATH is taken into account. For
      additional dependencies like "foo.o : bar.c" it is not.

> I'm all for removing this crap from suffix rules in Automake 1.8.

Great!

Bruno