Makefile question?
 

I have a Makefile with:

.PHONY: all clean distclean

all: $(LEXFILE) $(BINDIR)/$(APP)

where:

LEXFILE := lex.yy.c
APP = bridge
BINDIR = bin

If I redefine:

all: $(LEXFILE) $(OBJDIR)/%.o

where:

OBJDIR = obj

I get: make: *** No rule to make target `obj/%.o', needed by `all'. Stop.

Why?

the line all: $(LEXFILE) $(OBJDIR)/%.o is syntactically correct, but will not do what you want, you would need to check the documentation about how to use %.
In your case make is looking for a file named %.o in the dir obj.
Usually you need something like that:
%.ext1: %.ext2 where % can be replaced with a filename using ext1 and ext2 as target(result) and source.

Well, what did you mean by $(OBJDIR)/%.o? What should make have substitute with?