passing -j option to a sub-make

[Philippe HAUTION]

Hello,

We are using this kind of Makefile to launch several sub-makes (gmake 
3.79.1 on Solaris 8) :

.POSIX:
SHELL=/bin/ksh

SSP   = sources tools

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

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


It is running fine except in parallel mode with the -j N option. We get this 
warning :
"jobserver unavailable: using -j1.  Add `+' to parent make rule.". 
However, parallel mode works if we are launching gmake directly in any subdirectory.

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

Any idea ?

Regards,

--
Philippe Haution
EDF R&D
Département Méthodes d'Optimisation et de Simulation
1 Av du Général de Gaulle
92141 Clamart CEDEX