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GNU Make: Using % in a pattern-rule macro

SexyBachelor (41)
Hi,

I'm revising my code to make it a bit cleaner and right now I'm working on the makefile.

I'm having a problem with defining a pattern rule that uses % to access another variable.
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# program output name
OUT=a.out

# compiler flags
FLAGS=-ggdb -std=c++0x

# library dependencies
LIBS=-lSDL -lSDL_image -lboost_system -lboost_chrono -lGL

# where to store built objects
BIN=bin

# The objects to build
OBJECTS=Geometry.o Enemy.o Surface.o Player.o SDLWindow.o Path.o Territory.o Board.o Diminisher.o Main.o

# Header Dependencies per object
Geometry_H=Geometry.h
Enemy_H=Enemy.h $(Geometry_H)
Surface_H=Surface.h $(Geometry_H)
Player_H=Player.h $(Geometry_H) $(Surface_H)
SDLWindow_H=SDLWindow.h $(Surface_H)
Path_H=Path.h $(Geometry_H)
Territory_H=Territory.h $(Geometry_H)
Board_H=Board.h $(Territory_H) $(Geometry_H) $(Player_H) $(Path_H) $(Enemy_H)
Diminisher_H=Diminisher.h $(SDLWindow_H) $(Geometry_H) $(Surface_H) $(Board_H)
Main_H=$(Diminisher_H)

# make program
default: $(BIN) $(addprefix $(BIN)/, $(OBJECTS))
    g++ -o $(OUT) $(FLAGS) $(addprefix $(BIN)/, $(OBJECTS)) $(LIBS)

# create object bin directory
$(BIN):
    @ if [ ! -d "./$(BIN)" ]; then \
        mkdir $(BIN); \
    fi
    @echo "mkdir $(BIN)"

# command to make an object
$(BIN)/%.o: %.cpp $(%_H)
    g++ -o $@ $(FLAGS) -c $<

# delete all objects and program
clean:
    rm -rf $(BIN) 
    rm -f $(OUT)


Previously I had all the make rules explicitly written out. For example, Geometry read:

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$(BIN)/Geometry.o: Geometry.cpp $(Geometry_H)
    g++ -o $@ $(FLAGS) -c $<


The problem I'm having is in bold.

In the new code, $(%_H) isn't expanding to Geometry_H.
I've tried many other variants such as:
$($%_H)
$( $(value %)_H )

I'm hoping someone knows the correct syntax.

The project will still build with this code, but if I edit a header file and run make without cleaning first, make will not rebuild the objects that depend on this header as defined by the *_H variables.

The old code would rebuild the targets that depended on the edited header.
ne555 (10692)
What I use 
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#Header dependencies per object
#g++ -MM *.cpp
point.o: point.h
window.o: point.h geometric_algorithms.h
geometric_algorithms.o: point.h geometric_algorithms.h

%.o : %.cpp
	$(CXX) $< -c $(CPPFLAGS) -o $@

SexyBachelor (41)
Thank-you. That works.
Although I'm still curious as to why I can't use % inside a macro call.
SexyBachelor (41)
http://stackoverflow.com/questions/10867861/gnu-make-using-in-a-pattern-rule-macro

If anyone is interested in how to use the automatic variables in a macro call.
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