Makefile: pass CXX in making subdirectories

Makefile

@@ -14,7 +14,7 @@ R64COBJSPB= $(addsuffix x,  $(COBJSPB))
 
 COBJS     = $(COBJSPB) \
 			glueminisat/core/Solver.o glueminisat/simp/SimpSolver.o glueminisat/utils/System.o \
-			manyglucose/utils/System.o manyglucose/mtl/Clone.o manyglucose/core/Solver.o manyglucose/simp/SimpSolver.o manyglucose/parallel/PrdClauses.o manyglucose/parallel/PrdClausesQueueMgr.o manyglucose/parallel/SolverCompanion.o manyglucose/parallel/SharedCompanion.o manyglucose/parallel/PeriodClausesBuffer.o manyglucose/parallel/SolverConfiguration.o manyglucose/parallel/PrdClausesQueue.o manyglucose/parallel/ParallelSolver.o manyglucose/parallel/MultiSolvers.o \
+manyglucose/parallel/MultiSolvers.o manyglucose/parallel/ParallelSolver.o manyglucose/parallel/PrdClausesQueue.o manyglucose/parallel/SolverConfiguration.o manyglucose/parallel/PeriodClausesBuffer.o manyglucose/parallel/SharedCompanion.o manyglucose/parallel/SolverCompanion.o manyglucose/parallel/PrdClausesQueueMgr.o manyglucose/parallel/PrdClauses.o manyglucose/simp/SimpSolver.o manyglucose/core/Solver.o manyglucose/mtl/Clone.o manyglucose/utils/System.o \
 			es1sat/core/Solver.o es1sat/simp/SimpSolver.o \
 			ccminisat/core/Solver.o  ccminisat/simp/SimpSolver.o
 PCOBJS    = $(addsuffix p,  $(COBJS))
@@ -24,10 +24,10 @@ R64COBJS  = $(addsuffix x,  $(COBJS))
 
 EXEC      = naps
 
-#CXX       = g++6
-#LDFLAGS   += -Wl,-rpath=/usr/local/lib/gcc6
-CXX       ?= g++
+#CXX       = g++8
+LDFLAGS   += -L/usr/local/lib/g++8
 #CXX      = icpc
+CXX       ?= g++
 CFLAGS    = -Wall -ffloat-store 
 #CFLAGS   += -IADTs -include Global.h -include Main.h -D_FILE_OFFSET_BITS=64 
 #CFLAGS   += -IADTs -Iglueminisat -include Global.h -include Main.h -D_FILE_OFFSET_BITS=64 
@@ -116,29 +116,17 @@ glueminisat/simp/SimpSolver.od:
 glueminisat/simp/SimpSolver.ox:
 	MROOT=$(CURDIR)/glueminisat $(MAKE) -C $(CURDIR)/glueminisat/simp rx
 
-manyglucose/utils/System.o:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel
-
-manyglucose/utils/System.or:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel rs
-
-manyglucose/utils/System.od:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel d
-
-manyglucose/utils/System.ox:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel rx
-
 manyglucose/parallel/MultiSolvers.o:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel
+	$(MAKE) -C $(CURDIR)/manyglucose/parallel CXX=$(CXX)
 
 manyglucose/parallel/MultiSolvers.or:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel rs
+	$(MAKE) -C $(CURDIR)/manyglucose/parallel CXX=$(CXX) rs
 
 manyglucose/parallel/MultiSolvers.od:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel d
+	$(MAKE) -C $(CURDIR)/manyglucose/parallel CXX=$(CXX) d
 
 manyglucose/parallel/MultiSolvers.ox:
-	$(MAKE) -C $(CURDIR)/manyglucose/parallel rx
+	$(MAKE) -C $(CURDIR)/manyglucose/parallel CXX=$(CXX) rx
 
 es1sat/core/Solver.o: es1sat/core/Solver.cc
 	MROOT=$(CURDIR)/es1sat $(MAKE) -C $(CURDIR)/es1sat/core