Re: [PATCH] build: use automake's new $(AM_V_GEN) and $(AM_V_at) variables

[Ralf Wildenhues]

Hi Jim,

Jim Meyering writes:
> --- a/src/Makefile.am
> +++ b/src/Makefile.am
> @@ -290,26 +290,29 @@ editpl = sed -e 's,@''PERL''@,$(PERL),g'
> 
>  BUILT_SOURCES += dircolors.h
>  dircolors.h: dcgen dircolors.hin
> -     @rm -f $@ address@hidden
> -     $(PERL) -w -- $(srcdir)/dcgen $(srcdir)/dircolors.hin > address@hidden
> -     @chmod a-w address@hidden
> -     mv address@hidden $@
> +     $(AM_V_GEN)
> +     $(AM_V_at)rm -f $@ address@hidden
> +     $(AM_V_at)$(PERL) -w -- $(srcdir)/dcgen $(srcdir)/dircolors.hin > 
> address@hidden
> +     $(AM_V_at)chmod a-w address@hidden
> +     $(AM_V_at)mv address@hidden $@

Thanks for using these.  Note the $(AM_V_GEN) will expand to the empty string
with V=1 or --disable-silent-rules.  I am actually not sure whether any make
implementation fails hard upon empty rule commands, but a couple of them will
output a warning, such as FreeBSD:
  $(AM_V_GEN) expands to empty string

and AIX:
  make: 1254-053 Command "$(AM_V_GEN)" expands to empty string.

You might want to just prepend the $(AM_V_GEN) to the next command, without
anything in-between.  We might want to document this better in automake.texi.

Thanks!
Ralf