Strictness in syntax of Makefiles

Hello all,

I'm still learning my ropes at writing Makefiles and make descriptor files. I can't seem to get the filter-out option working properly. Despite filling out

FILTER_OUT = somefile.cpp SRC_CC += $(filter-out $(FILTER_OUT),$(notdir $(wildcard $(SRC_DIR)/subdirs/*.cpp)))

the build system continues to add these to the set of files to be built.

Next, most of the screen is bombarded with unused-variable and unused-function warnings. I tried to suppress them as mentioned in the build system manual with the CC_OPT += -Wunused-function -Wunused-variable

Build system still throws the above warnings. Are the spacing and/or use of commas crucial to the build system?

Thanks and regards, Aditya