Re: passing -j option to a sub-make

[Paul D. Smith]

%% Philippe HAUTION <address@hidden> writes:

  ph> LOOP = @for ssp in $(SSP); do \
  ph>           (echo $$ssp :; cd $$ssp; \
  ph>            if [[ ! -f Makefile.dep ]]; then \
  ph>              $(MAKE) depend; \
  ph>            fi; \
  ph>            $(MAKE) $@ || return 1) \
  ph>         done

  ph> debug release clean cleand cleanr refresh depend pure :
  ph>     $(LOOP)


  ph> It is running fine except in parallel mode with the -j N
  ph> option. We get this warning : "jobserver unavailable: using -j1.
  ph> Add `+' to parent make rule.".

  ph> The manual says this warning means that the parent has troubles
  ph> determining the child is a make, which is quite confusing since
  ph> the MAKE variable seems properly used.

Make only looks at the unexpanded command line and searches for the
strings '$(MAKE)' or '${MAKE}'.  It does not look at the expansion of
the command line (it cannot, since after expansion obviously there will
be no $(MAKE) or ${MAKE}... they are expanded!)

Your unexpanded command line is the string '$(LOOP)', which obviously
does not contain the text '$(MAKE)' or '${MAKE}'.

Just exactly as the error message says, you need to add a "+" to the
beginning of the rule.  Change:

 LOOP = @for ssp in $(SSP); do \
        ...

to

 LOOP = address@hidden ssp in $(SSP); do \
        ...

-- 
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 Paul D. Smith <address@hidden>          Find some GNU make tips at:
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