# tools/pybind11Tools.cmake -- Build system for the pybind11 modules # # Copyright (c) 2015 Wenzel Jakob # # All rights reserved. Use of this source code is governed by a # BSD-style license that can be found in the LICENSE file. cmake_minimum_required(VERSION 2.8.12) # Add a CMake parameter for choosing a desired Python version if(NOT PYBIND11_PYTHON_VERSION) set(PYBIND11_PYTHON_VERSION "" CACHE STRING "Python version to use for compiling modules") endif() set(Python_ADDITIONAL_VERSIONS 3.7 3.6 3.5 3.4) find_package(PythonLibsNew ${PYBIND11_PYTHON_VERSION} REQUIRED) include(CheckCXXCompilerFlag) include(CMakeParseArguments) function(select_cxx_standard) if(NOT MSVC AND NOT PYBIND11_CPP_STANDARD) 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(PYBIND11_CPP_STANDARD -std=c++14) elseif (HAS_CPP11_FLAG) set(PYBIND11_CPP_STANDARD -std=c++11) else() message(FATAL_ERROR "Unsupported compiler -- pybind11 requires C++11 support!") endif() set(PYBIND11_CPP_STANDARD ${PYBIND11_CPP_STANDARD} CACHE STRING "C++ standard flag, e.g. -std=c++11 or -std=c++14. Defaults to latest available." FORCE) endif() endfunction() # Internal: find the appropriate LTO flag for this compiler macro(_pybind11_find_lto_flag output_var prefer_thin_lto) if(${prefer_thin_lto}) # Check for ThinLTO support (Clang) check_cxx_compiler_flag("-flto=thin" HAS_THIN_LTO_FLAG) set(${output_var} $<${HAS_THIN_LTO_FLAG}:-flto=thin>) endif() if(NOT ${prefer_thin_lto} OR NOT HAS_THIN_LTO_FLAG) if(NOT CMAKE_CXX_COMPILER_ID MATCHES "Intel") # Check for Link Time Optimization support (GCC/Clang) check_cxx_compiler_flag("-flto" HAS_LTO_FLAG) set(${output_var} $<${HAS_LTO_FLAG}:-flto>) else() # Intel equivalent to LTO is called IPO check_cxx_compiler_flag("-ipo" HAS_IPO_FLAG) set(${output_var} $<${HAS_IPO_FLAG}:-ipo>) endif() endif() endmacro() # Build a Python extension module: # pybind11_add_module( [MODULE | SHARED] [EXCLUDE_FROM_ALL] # [NO_EXTRAS] [THIN_LTO] source1 [source2 ...]) # function(pybind11_add_module target_name) set(options MODULE SHARED EXCLUDE_FROM_ALL NO_EXTRAS THIN_LTO) cmake_parse_arguments(ARG "${options}" "" "" ${ARGN}) if(ARG_MODULE AND ARG_SHARED) message(FATAL_ERROR "Can't be both MODULE and SHARED") elseif(ARG_SHARED) set(lib_type SHARED) else() set(lib_type MODULE) endif() if(ARG_EXCLUDE_FROM_ALL) set(exclude_from_all EXCLUDE_FROM_ALL) endif() add_library(${target_name} ${lib_type} ${exclude_from_all} ${ARG_UNPARSED_ARGUMENTS}) target_include_directories(${target_name} PRIVATE ${PYBIND11_INCLUDE_DIR} # from project CMakeLists.txt PRIVATE ${pybind11_INCLUDE_DIR} # from pybind11Config PRIVATE ${PYTHON_INCLUDE_DIRS}) # The prefix and extension are provided by FindPythonLibsNew.cmake set_target_properties(${target_name} PROPERTIES PREFIX "${PYTHON_MODULE_PREFIX}") set_target_properties(${target_name} PROPERTIES SUFFIX "${PYTHON_MODULE_EXTENSION}") if(WIN32 OR CYGWIN) # Link against the Python shared library on Windows target_link_libraries(${target_name} PRIVATE ${PYTHON_LIBRARIES}) elseif(APPLE) # It's quite common to have multiple copies of the same Python version # installed on one's system. E.g.: one copy from the OS and another copy # that's statically linked into an application like Blender or Maya. # If we link our plugin library against the OS Python here and import it # into Blender or Maya later on, this will cause segfaults when multiple # conflicting Python instances are active at the same time (even when they # are of the same version). # Windows is not affected by this issue since it handles DLL imports # differently. The solution for Linux and Mac OS is simple: we just don't # link against the Python library. The resulting shared library will have # missing symbols, but that's perfectly fine -- they will be resolved at # import time. target_link_libraries(${target_name} PRIVATE "-undefined dynamic_lookup") if(ARG_SHARED) # Suppress CMake >= 3.0 warning for shared libraries set_target_properties(${target_name} PROPERTIES MACOSX_RPATH ON) endif() endif() select_cxx_standard() if(NOT MSVC) # Make sure C++11/14 are enabled target_compile_options(${target_name} PUBLIC ${PYBIND11_CPP_STANDARD}) endif() if(ARG_NO_EXTRAS) return() endif() if(NOT MSVC) # Enable link time optimization and set the default symbol # visibility to hidden (very important to obtain small binaries) string(TOUPPER "${CMAKE_BUILD_TYPE}" U_CMAKE_BUILD_TYPE) if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG) # Link Time Optimization if(NOT CYGWIN) _pybind11_find_lto_flag(lto_flag ARG_THIN_LTO) target_compile_options(${target_name} PRIVATE ${lto_flag}) endif() # Default symbol visibility target_compile_options(${target_name} PRIVATE "-fvisibility=hidden") # Strip unnecessary sections of the binary on Linux/Mac OS if(CMAKE_STRIP) if(APPLE) add_custom_command(TARGET ${target_name} POST_BUILD COMMAND ${CMAKE_STRIP} -x $) else() add_custom_command(TARGET ${target_name} POST_BUILD COMMAND ${CMAKE_STRIP} $) endif() endif() endif() elseif(MSVC) # /MP enables multithreaded builds (relevant when there are many files), /bigobj is # needed for bigger binding projects due to the limit to 64k addressable sections target_compile_options(${target_name} PRIVATE /MP /bigobj) # Enforce link time code generation on MSVC, except in debug mode target_compile_options(${target_name} PRIVATE $<$>:/GL>) # Fancy generator expressions don't work with linker flags, for reasons unknown set_property(TARGET ${target_name} APPEND_STRING PROPERTY LINK_FLAGS_RELEASE /LTCG) set_property(TARGET ${target_name} APPEND_STRING PROPERTY LINK_FLAGS_MINSIZEREL /LTCG) set_property(TARGET ${target_name} APPEND_STRING PROPERTY LINK_FLAGS_RELWITHDEBINFO /LTCG) endif() endfunction()