ifdef usage in C preprocessor & Makefile

http://en.wikipedia.org/wiki/C_preprocessor
http://www.gnu.org/software/make/manual/make.html

The error syntax for C preprocessor is like:

#error "Wrong!!!"

For Makefile is like:

$(error Wrong...)

To use a ifeq OR logic, using filter instead...

ifeq ($(ARCH), $(filter $(ARCH),LINUX-NATIVE LINUX-I686))