Embedded Macro References

Macro references can be embedded within other references (not supported in previous versions of make)..

$(CPPFLAGS$(TARGET_ARCH))

The += assignment appends the indicated string to any previous value for the macro.

In which case they are expanded from innermost to outermost. With the following definitions, make will supply the correct symbol definition for (for example) a Sun-4 system.

CPPFLAGS-sun4 = -DSUN4 
CPPFLAGS += $(CPPFLAGS-$(TARGET_ARCH))