How do i point make to use a particular system library in a build?

I've tr开发者_StackOverflowied putting this in the local Makefile :

INCLUDE +=  -I/opt/local/include

and tried putting this in the mozconfig:

export CFLAGS="-I/opt/local/include" export CXXFLAGS="-I/opt/local/include"

But i still get :

error: portaudio.h: No such file or directory

How do i get make to find the right libraries?

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Add these to source//config/myconfig.mk

CFLAGS += -I/path/to/includes -L/path/to/libs -l
CXXFLAGS += -I/path/to/includes -L/path/to/libs -l