Boost.Python Makefile to CMakLists.txt - makefile

Question

I wrote some C++ files to create a shared library, and here is my Makefile
PYTHON_VERSION = 3.6
PYTHON_HOME_PATH = /Library/Frameworks/Python.framework/Versions
PYTHON_INCLUDE = $(PYTHON_HOME_PATH)/$(PYTHON_VERSION)
BOOST_INC = /usr/local/Cellar/boost/1.67.0_1/include
BOOST_LIB = /usr/local/Cellar/boost/1.67.0_1/lib
BOOST_PYTHON_LIB = /usr/local/Cellar/boost-python3/1.67.0_1/lib/
TARGET = main
EXTEND_FILE = main_ext
$(TARGET).so:$(TARGET).o
g++ -shared depend.o -L$(BOOST_LIB) -L$(BOOST_PYTHON_LIB) -lboost_python3 `python3.6m-config --libs --ldflags` -o depend_ext.so
g++ -shared depend.o $(TARGET).o -L$(BOOST_LIB) -L$(BOOST_PYTHON_LIB) -lboost_python3 `python3.6m-config --libs --ldflags` -o $(TARGET).so
mv $(TARGET).so $(EXTEND_FILE).so
depend.o:depend.cpp
g++ `python3.6m-config --include` -fPIC -c depend.cpp -O3 -std=c++11
$(TARGET).o:$(TARGET).cpp
g++ `python3.6m-config --include` -fPIC -c depend.cpp $(TARGET).cpp -O3 -std=c++11
clean:
rm *.so *.o
The Makefile can generate the .so file. And my CMakeLists.txt is
cmake_minimum_required(VERSION 3.8)
project(Simulator)
set(CMAKE_CXX_STANDARD 11)
set(SOURCE_FILES depend.cpp depend.h main.cpp main.h)
add_executable(Simulator ${SOURCE_FILES})
set(Boost_INCLUDE_DIRS /usr/local/Cellar/boost/1.67.0_1/include)
set(Boost_LIBRARIES /usr/local/Cellar/boost/1.67.0_1/lib)
set(BOOST_PYTHON_LIB /usr/local/Cellar/boost-python3/1.67.0_1/lib/)
find_package(Boost COMPONENTS filesystem system date_time python REQUIRED)
message("--> Include dirs of boost: " ${Boost_INCLUDE_DIRS} )
message("--> Libs of boost: " ${Boost_LIBRARIES} )
find_package(PythonLibs 3.6 REQUIRED)
message("--> Include dirs of Python: " ${PYTHON_INCLUDE_DIRS} )
message("--> Libs of Python: " ${PYTHON_LIBRARIES} )
include_directories(
${Boost_INCLUDE_DIRS}
${PYTHON_INCLUDE_DIRS}
)
target_link_libraries(Simulator
${Boost_LIBRARIES}
${PYTHON_LIBRARIES}
${BOOST_PYTHON_LIB}
)
But running CMake gives the following errors
CMake Error at /usr/local/Cellar/cmake/3.10.2/share/cmake/Modules/FindBoost.cmake:1928 (message):
Unable to find the requested Boost libraries.
Boost version: 1.67.0
Boost include path: /usr/local/include
Could not find the following Boost libraries:
boost_python3
I want to build it with Python3 and I have already install boost.python3. How can I fix it?

Answer 1

I think the problem is that Homebrew installs boost_python under a separate directory (i.e. /usr/local/Cellar/boost-python3/1.67.0_1/) which is different from the rest of the Boost installation (i.e. /usr/local/Cellar/boost/1.67.0_1).
I'm not on a Mac, thus I'm not exactly certain of the actual directory structure and how much can be done with symlinks (symlinking the Boost Python component directories back into the main Boost installation dir).
So, I built and installed (on Ubuntu Linux) from source the latest Boost version (1.68) using
./bootstrap.sh --prefix=/bulk/workbench/boost/install --with-python=python3
All components ended up under the include and lib directories in /bulk/workbench/boost/install. Providing that during CMake configuration as in
cmake -DBoost_ROOT=/bulk/workbench/boost/install [path-to-my-project-source-dir]
and using this in my CMakeLists.txt
find_package(Boost COMPONENTS python REQUIRED)
it was able to find my boost_python module.
Basically, unless you're able to twist the Homebrew installation, it might be more straightforward to build your own Boost.