Re: for sub in $(SUBMAKES); but $(SUBMAKES) is empty

[Alexander Farber]

Hi,

thanks for your help! But aside from the discussion
about the recursive makefiles (I really don't have a
choice at the moment and have to use them ), is this 
below supposed to work or not?


    linux72:afarber {331} cat Makefile
    SUBMAKES=

    all:
            for i in $(SUBMAKES); do \
                    echo $$i; \
            done

It fails for me on some Linux PCs and HP-UX machines 
(with bash 2.05) and works on others (bash 2.05b, 3.0):

    boclu21:afarber {53} gmake
    for i in ; do \
            echo $i; \
    done
    /bin/sh: -c: line 1: syntax error near unexpected token `;'
    /bin/sh: -c: line 1: `for i in ; do  echo $i;  done'
    gmake: *** [all] Error 2

Do I really have to modify my makefiles to contain:

    all clean: $(SUBMAKES)
            test -z "$(SUBMAKES)" || for sub in "$(SUBMAKES)"; do \
                    $(MAKE) -f $$sub $@; \
            done

This feels so awkward to me. How do others deal with this?

Regards
Alex


On Fri, Sep 17, 2004 at 12:11:54PM -0400, Noel Yap wrote:
> Short-term answer: you could change the action to test the contents of 
> $(SUBMAKES) prior to doing the for loop:
> 
>       if [ ! -z "$(SUBMAKES)" ]
>       then
>               for sub in ...
>               do
>               done
>       fi
> 
> 
> Long-term answer: don't use recursive make.  See 
> http://aegis.sourceforge.net/auug97.pdf.
> 
> Alexander Farber wrote:
> >
> >does anybody please know, how to deal with the following problem?
> >I have several GNU makefiles which call other makefiles like this:
> >
> >    MMPFILES =
> >    SUBMAKES = $(foreach FILE, $(MMPFILES), $(FILE).$(PLAT).mbs)
> >    all clean: $(SUBMAKES)
> >         for sub in $(SUBMAKES); do \
> >                 $(MAKE) -f $$sub $@; \
> >         done
> >
> >For few of the makefiles the MMPFILES variable is empty (as above).
> >This still works on some Linux-PC's here but fails on others:
> >
> >    boclu21:group {557} gmake -f Makefile.WINS.mbs
> >    for sub in ; do \
> >         gmake -f $sub all; \
> >    done
> >    /bin/sh: -c: line 1: syntax error near unexpected token `;'
> >    /bin/sh: -c: line 1: `for sub in ; do  gmake -f $sub all;  done'
> >    gmake: *** [all] Error 2
> >
> >Looks like the reason is the bash version. 
> >The line below works fine on 2.05b.0(1):
> >
> >    bolinux72:calimero {321} for sub in; do echo gmake -f $sub all; done
> >    bolinux72:calimero {322} 
> > 
> >But on the PC with the GNU bash 2.05.8(1) it fails:
> >
> >    boclu21:group {323} for sub in; do echo gmake -f $sub all; done
> >    bash: syntax error near unexpected token `;'