$ ./configure
CXXFLAGS/LDFLAGS checking...
warning: pkg-config or pc files not found, lib detection may be inaccurate.
checking for vapoursynth headers...
checking for OpenCL...

settings...
CXX          = g++
LD           = g++
STRIP        = strip
CXXFLAGS     = -O2 -std=gnu++11 -Wall -Wno-unused-local-typedefs -I. -I./shared -I./include   -I/usr/local/Cellar/vapoursynth/36/include/vapoursynth -I/usr/local/Cellar/zimg/2.4/include
LDFLAGS      = -shared -dynamiclib -Wl,-undefined,suppress -Wl,-read_only_relocs,suppress -Wl,-flat_namespace
LIBS         =  -framework OpenCL
LIBNAME      = libknlmeanscl.dylib
install path = /usr/local/lib/vapoursynth
configure finished.
$ make
g++ -O2 -std=gnu++11 -Wall -Wno-unused-local-typedefs -I. -I./shared -I./include   -I/usr/local/Cellar/vapoursynth/36/include/vapoursynth -I/usr/local/Cellar/zimg/2.4/include -c KNLMeansCL/KNLMeansCL.cpp -o KNLMeansCL/KNLMeansCL.o
g++ -o libknlmeanscl.dylib -shared -dynamiclib -Wl,-undefined,suppress -Wl,-read_only_relocs,suppress -Wl,-flat_namespace   KNLMeansCL/KNLMeansCL.o -framework OpenCL
ld: warning: -read_only_relocs cannot be used with x86_64