Skip to content

P
pybind11
Commit 24ddf4b3 by Dean Moldovan
Options

Update CMake build documentation

parent 49720f03
Showing with 20 additions and 138 deletions
docs/compiling.rst
...@@ -26,146 +26,28 @@ Building with cppimport ...@@ -26,146 +26,28 @@ Building with cppimport
Building with CMake Building with CMake
=================== ===================
For C++ codebases that already have an existing CMake-based build system, the For C++ codebases that have an existing CMake-based build system, a Python
following snippet should be a good starting point to create bindings across extension module can be created with just a few lines of code:
platforms. It assumes that the code is located in a file named
:file:`example.cpp`, and that the pybind11 repository is located in a
subdirectory named :file:`pybind11`.
.. code-block:: cmake .. code-block:: cmake
cmake_minimum_required(VERSION 2.8) cmake_minimum_required(VERSION 2.8.12)
project(example) project(example)
# Add a CMake parameter for choosing a desired Python version add_subdirectory(pybind11)
set(EXAMPLE_PYTHON_VERSION "" CACHE STRING pybind11_add_module(example example.cpp)
"Python version to use for compiling the example library")
This assumes that the pybind11 repository is located in a subdirectory named
include(CheckCXXCompilerFlag) :file:`pybind11` and that the code is located in a file named :file:`example.cpp`.
The CMake command ``add_subdirectory`` will import a function with the signature
# Set a default build configuration if none is specified. ``pybind11_add_module(<name> source1 [source2 ...])``. It will take care of all
# 'MinSizeRel' produces the smallest binaries the details needed to build a Python extension module on any platform.
if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
message(STATUS "Setting build type to 'MinSizeRel' as none was specified.") The target Python version can be selected by setting the ``PYBIND11_PYTHON_VERSION``
set(CMAKE_BUILD_TYPE MinSizeRel CACHE STRING "Choose the type of build." FORCE) variable before adding the pybind11 subdirectory. Alternatively, an exact Python
set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release" installation can be specified by setting ``PYTHON_EXECUTABLE``.
"MinSizeRel" "RelWithDebInfo")
endif() A working sample project, including a way to invoke CMake from :file:`setup.py` for
string(TOUPPER "${CMAKE_BUILD_TYPE}" U_CMAKE_BUILD_TYPE) PyPI integration, can be found in the [cmake_example]_ repository.
# Try to autodetect Python (can be overridden manually if needed) .. [cmake_example] https://github.com/dean0x7d/pybind11_cmake_example
set(Python_ADDITIONAL_VERSIONS 3.4 3.5 3.6 3.7)
if (NOT ${EXAMPLE_PYTHON_VERSION} STREQUAL "")
find_package(PythonLibs ${EXAMPLE_PYTHON_VERSION} EXACT)
if (NOT PYTHONLIBS_FOUND)
find_package(PythonLibs ${EXAMPLE_PYTHON_VERSION} REQUIRED)
endif()
else()
find_package(PythonLibs REQUIRED)
endif()
# The above sometimes returns version numbers like "3.4.3+";
# the "+" must be removed for the next lines to work
string(REPLACE "+" "" PYTHONLIBS_VERSION_STRING "+${PYTHONLIBS_VERSION_STRING}")
# Uncomment the following line if you will also require a matching Python interpreter
# find_package(PythonInterp ${PYTHONLIBS_VERSION_STRING} EXACT REQUIRED)
if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
CHECK_CXX_COMPILER_FLAG("-std=c++14" HAS_CPP14_FLAG)
CHECK_CXX_COMPILER_FLAG("-std=c++11" HAS_CPP11_FLAG)
if (HAS_CPP14_FLAG)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
elseif (HAS_CPP11_FLAG)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
else()
message(FATAL_ERROR "Unsupported compiler -- at least C++11 support is needed!")
endif()
# Enable link time optimization and set the default symbol
# visibility to hidden (very important to obtain small binaries)
if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
# Default symbol visibility
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden")
# Check for Link Time Optimization support
CHECK_CXX_COMPILER_FLAG("-flto" HAS_LTO_FLAG)
if (HAS_LTO_FLAG)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -flto")
endif()
endif()
endif()
# Include path for Python header files
include_directories(${PYTHON_INCLUDE_DIR})
# Include path for pybind11 header files -- this may need to be
# changed depending on your setup
include_directories(${PROJECT_SOURCE_DIR}/pybind11/include)
# Create the binding library
add_library(example SHARED
example.cpp
# ... extra files go here ...
)
# Don't add a 'lib' prefix to the shared library
set_target_properties(example PROPERTIES PREFIX "")
if (WIN32)
if (MSVC)
# /MP enables multithreaded builds (relevant when there are many files), /bigobj is
# needed for bigger binding projects due to the limit to 64k addressable sections
set_property(TARGET example APPEND PROPERTY COMPILE_OPTIONS /MP /bigobj)
# Enforce size-based optimization and link time code generation on MSVC
# (~30% smaller binaries in experiments); do nothing in debug mode.
set_property(TARGET example APPEND PROPERTY COMPILE_OPTIONS
"$<$<CONFIG:Release>:/Os>" "$<$<CONFIG:Release>:/GL>"
"$<$<CONFIG:MinSizeRel>:/Os>" "$<$<CONFIG:MinSizeRel>:/GL>"
"$<$<CONFIG:RelWithDebInfo>:/Os>" "$<$<CONFIG:RelWithDebInfo>:/GL>"
)
set_property(TARGET example APPEND_STRING PROPERTY LINK_FLAGS_RELEASE "/LTCG ")
set_property(TARGET example APPEND_STRING PROPERTY LINK_FLAGS_MINSIZEREL "/LTCG ")
set_property(TARGET example APPEND_STRING PROPERTY LINK_FLAGS_RELWITHDEBINFO "/LTCG ")
endif()
# .PYD file extension on Windows
set_target_properties(example PROPERTIES SUFFIX ".pyd")
# Link against the Python shared library
target_link_libraries(example ${PYTHON_LIBRARY})
elseif (UNIX)
# It's quite common to have multiple copies of the same Python version
# installed on one's system. E.g.: one copy from the OS and another copy
# that's statically linked into an application like Blender or Maya.
# If we link our plugin library against the OS Python here and import it
# into Blender or Maya later on, this will cause segfaults when multiple
# conflicting Python instances are active at the same time (even when they
# are of the same version).
# Windows is not affected by this issue since it handles DLL imports
# differently. The solution for Linux and Mac OS is simple: we just don't
# link against the Python library. The resulting shared library will have
# missing symbols, but that's perfectly fine -- they will be resolved at
# import time.
# .SO file extension on Linux/Mac OS
set_target_properties(example PROPERTIES SUFFIX ".so")
# Strip unnecessary sections of the binary on Linux/Mac OS
if(APPLE)
set_target_properties(example PROPERTIES MACOSX_RPATH ".")
set_target_properties(example PROPERTIES LINK_FLAGS "-undefined dynamic_lookup ")
if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
add_custom_command(TARGET example POST_BUILD
COMMAND strip -u -r ${PROJECT_BINARY_DIR}/example.so)
endif()
else()
if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
add_custom_command(TARGET example POST_BUILD
COMMAND strip ${PROJECT_BINARY_DIR}/example.so)
endif()
endif()
endif()
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment