make don't know how to make CXXFLAGS. Stop

I am very new to both FreeBSD and compiling code from source and would really appreciate any help. I am trying to compile [fastText](https://github.com/facebookresearch/fastText) from source. When I execute the make command it returns the following message: make don't know how to make CXXFLAGS. Stop Here are first few lines from Makefile(complete file is available on the fastText github repo mentioned above): CXX = c++ CXXFLAGS = -pthread -std=c++0x OBJS = args.o dictionary.o matrix.o vector.o model.o utils.o INCLUDES = -I. opt: CXXFLAGS += -O3 -funroll-loops opt: fasttext debug: CXXFLAGS += -g -O0 -fno-inline debug: fasttext FreeBSD version: 10.3 FreeBSD clang version: 3.4.1 gmake version: 4.1_2