1# tools/pybind11Tools.cmake -- Build system for the pybind11 modules
2#
3# Copyright (c) 2015 Wenzel Jakob <wenzel@inf.ethz.ch>
4#
5# All rights reserved. Use of this source code is governed by a
6# BSD-style license that can be found in the LICENSE file.
7
8cmake_minimum_required(VERSION 2.8.12)
9
10# Add a CMake parameter for choosing a desired Python version
11if(NOT PYBIND11_PYTHON_VERSION)
12 set(PYBIND11_PYTHON_VERSION "" CACHE STRING "Python version to use for compiling modules")
13endif()
14
15set(Python_ADDITIONAL_VERSIONS 3.7 3.6 3.5 3.4)
16find_package(PythonLibsNew ${PYBIND11_PYTHON_VERSION} REQUIRED)
17
18include(CheckCXXCompilerFlag)
19include(CMakeParseArguments)
20
21function(select_cxx_standard)
22 if(NOT MSVC AND NOT PYBIND11_CPP_STANDARD)
23 check_cxx_compiler_flag("-std=c++14" HAS_CPP14_FLAG)
24 check_cxx_compiler_flag("-std=c++11" HAS_CPP11_FLAG)
25
26 if (HAS_CPP14_FLAG)
27 set(PYBIND11_CPP_STANDARD -std=c++14)
28 elseif (HAS_CPP11_FLAG)
29 set(PYBIND11_CPP_STANDARD -std=c++11)
30 else()
31 message(FATAL_ERROR "Unsupported compiler -- pybind11 requires C++11 support!")
32 endif()
33
34 set(PYBIND11_CPP_STANDARD ${PYBIND11_CPP_STANDARD} CACHE STRING
35 "C++ standard flag, e.g. -std=c++11 or -std=c++14. Defaults to latest available." FORCE)
36 endif()
37endfunction()
38
39# Checks whether the given CXX/linker flags can compile and link a cxx file. cxxflags and
40# linkerflags are lists of flags to use. The result variable is a unique variable name for each set
41# of flags: the compilation result will be cached base on the result variable. If the flags work,
42# sets them in cxxflags_out/linkerflags_out internal cache variables (in addition to ${result}).
43function(_pybind11_return_if_cxx_and_linker_flags_work result cxxflags linkerflags cxxflags_out linkerflags_out)
44 set(CMAKE_REQUIRED_LIBRARIES ${linkerflags})
45 check_cxx_compiler_flag("${cxxflags}" ${result})
46 if (${result})
47 set(${cxxflags_out} "${cxxflags}" CACHE INTERNAL "" FORCE)
48 set(${linkerflags_out} "${linkerflags}" CACHE INTERNAL "" FORCE)
49 endif()
50endfunction()
51
52# Internal: find the appropriate link time optimization flags for this compiler
53function(_pybind11_add_lto_flags target_name prefer_thin_lto)
54 if (NOT DEFINED PYBIND11_LTO_CXX_FLAGS)
55 set(PYBIND11_LTO_CXX_FLAGS "" CACHE INTERNAL "")
56 set(PYBIND11_LTO_LINKER_FLAGS "" CACHE INTERNAL "")
57
58 if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
59 set(cxx_append "")
60 set(linker_append "")
61 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT APPLE)
62 # Clang Gold plugin does not support -Os; append -O3 to MinSizeRel builds to override it
63 set(linker_append ";$<$<CONFIG:MinSizeRel>:-O3>")
64 elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
65 set(cxx_append ";-fno-fat-lto-objects")
66 endif()
67
68 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND prefer_thin_lto)
69 _pybind11_return_if_cxx_and_linker_flags_work(HAS_FLTO_THIN
70 "-flto=thin${cxx_append}" "-flto=thin${linker_append}"
71 PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
72 endif()
73
74 if (NOT HAS_FLTO_THIN)
75 _pybind11_return_if_cxx_and_linker_flags_work(HAS_FLTO
76 "-flto${cxx_append}" "-flto${linker_append}"
77 PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
78 endif()
79 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Intel")
80 # Intel equivalent to LTO is called IPO
81 _pybind11_return_if_cxx_and_linker_flags_work(HAS_INTEL_IPO
82 "-ipo" "-ipo" PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
83 elseif(MSVC)
84 # cmake only interprets libraries as linker flags when they start with a - (otherwise it
85 # converts /LTCG to \LTCG as if it was a Windows path). Luckily MSVC supports passing flags
86 # with - instead of /, even if it is a bit non-standard:
87 _pybind11_return_if_cxx_and_linker_flags_work(HAS_MSVC_GL_LTCG
88 "/GL" "-LTCG" PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
89 endif()
90
91 if (PYBIND11_LTO_CXX_FLAGS)
92 message(STATUS "LTO enabled")
93 else()
94 message(STATUS "LTO disabled (not supported by the compiler and/or linker)")
95 endif()
96 endif()
97
98 # Enable LTO flags if found, except for Debug builds
99 if (PYBIND11_LTO_CXX_FLAGS)
100 target_compile_options(${target_name} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:${PYBIND11_LTO_CXX_FLAGS}>")
101 endif()
102 if (PYBIND11_LTO_LINKER_FLAGS)
103 target_link_libraries(${target_name} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:${PYBIND11_LTO_LINKER_FLAGS}>")
104 endif()
105endfunction()
106
107# Build a Python extension module:
108# pybind11_add_module(<name> [MODULE | SHARED] [EXCLUDE_FROM_ALL]
109# [NO_EXTRAS] [THIN_LTO] source1 [source2 ...])
110#
111function(pybind11_add_module target_name)
112 set(options MODULE SHARED EXCLUDE_FROM_ALL NO_EXTRAS THIN_LTO)
113 cmake_parse_arguments(ARG "${options}" "" "" ${ARGN})
114
115 if(ARG_MODULE AND ARG_SHARED)
116 message(FATAL_ERROR "Can't be both MODULE and SHARED")
117 elseif(ARG_SHARED)
118 set(lib_type SHARED)
119 else()
120 set(lib_type MODULE)
121 endif()
122
123 if(ARG_EXCLUDE_FROM_ALL)
124 set(exclude_from_all EXCLUDE_FROM_ALL)
125 endif()
126
127 add_library(${target_name} ${lib_type} ${exclude_from_all} ${ARG_UNPARSED_ARGUMENTS})
128
129 target_include_directories(${target_name}
130 PRIVATE ${PYBIND11_INCLUDE_DIR} # from project CMakeLists.txt
131 PRIVATE ${pybind11_INCLUDE_DIR} # from pybind11Config
132 PRIVATE ${PYTHON_INCLUDE_DIRS})
133
134 # The prefix and extension are provided by FindPythonLibsNew.cmake
135 set_target_properties(${target_name} PROPERTIES PREFIX "${PYTHON_MODULE_PREFIX}")
136 set_target_properties(${target_name} PROPERTIES SUFFIX "${PYTHON_MODULE_EXTENSION}")
137
138 if(WIN32 OR CYGWIN)
139 # Link against the Python shared library on Windows
140 target_link_libraries(${target_name} PRIVATE ${PYTHON_LIBRARIES})
141 elseif(APPLE)
142 # It's quite common to have multiple copies of the same Python version
143 # installed on one's system. E.g.: one copy from the OS and another copy
144 # that's statically linked into an application like Blender or Maya.
145 # If we link our plugin library against the OS Python here and import it
146 # into Blender or Maya later on, this will cause segfaults when multiple
147 # conflicting Python instances are active at the same time (even when they
148 # are of the same version).
149
150 # Windows is not affected by this issue since it handles DLL imports
151 # differently. The solution for Linux and Mac OS is simple: we just don't
152 # link against the Python library. The resulting shared library will have
153 # missing symbols, but that's perfectly fine -- they will be resolved at
154 # import time.
155
156 target_link_libraries(${target_name} PRIVATE "-undefined dynamic_lookup")
157
158 if(ARG_SHARED)
159 # Suppress CMake >= 3.0 warning for shared libraries
160 set_target_properties(${target_name} PROPERTIES MACOSX_RPATH ON)
161 endif()
162 endif()
163
164 select_cxx_standard()
165 if(NOT MSVC)
166 # Make sure C++11/14 are enabled
167 target_compile_options(${target_name} PUBLIC ${PYBIND11_CPP_STANDARD})
168 endif()
169
170 if(ARG_NO_EXTRAS)
171 return()
172 endif()
173
174 _pybind11_add_lto_flags(${target_name} ${ARG_THIN_LTO})
175
176 if (NOT MSVC AND NOT ${CMAKE_BUILD_TYPE} MATCHES Debug)
177 # Set the default symbol visibility to hidden (very important to obtain small binaries)
178 target_compile_options(${target_name} PRIVATE "-fvisibility=hidden")
179
180 # Strip unnecessary sections of the binary on Linux/Mac OS
181 if(CMAKE_STRIP)
182 if(APPLE)
183 add_custom_command(TARGET ${target_name} POST_BUILD
184 COMMAND ${CMAKE_STRIP} -x $<TARGET_FILE:${target_name}>)
185 else()
186 add_custom_command(TARGET ${target_name} POST_BUILD
187 COMMAND ${CMAKE_STRIP} $<TARGET_FILE:${target_name}>)
188 endif()
189 endif()
190 endif()
191
192 if(MSVC)
193 # /MP enables multithreaded builds (relevant when there are many files), /bigobj is
194 # needed for bigger binding projects due to the limit to 64k addressable sections
195 target_compile_options(${target_name} PRIVATE /MP /bigobj)
196 endif()
197endfunction()
2#
3# Copyright (c) 2015 Wenzel Jakob <wenzel@inf.ethz.ch>
4#
5# All rights reserved. Use of this source code is governed by a
6# BSD-style license that can be found in the LICENSE file.
7
8cmake_minimum_required(VERSION 2.8.12)
9
10# Add a CMake parameter for choosing a desired Python version
11if(NOT PYBIND11_PYTHON_VERSION)
12 set(PYBIND11_PYTHON_VERSION "" CACHE STRING "Python version to use for compiling modules")
13endif()
14
15set(Python_ADDITIONAL_VERSIONS 3.7 3.6 3.5 3.4)
16find_package(PythonLibsNew ${PYBIND11_PYTHON_VERSION} REQUIRED)
17
18include(CheckCXXCompilerFlag)
19include(CMakeParseArguments)
20
21function(select_cxx_standard)
22 if(NOT MSVC AND NOT PYBIND11_CPP_STANDARD)
23 check_cxx_compiler_flag("-std=c++14" HAS_CPP14_FLAG)
24 check_cxx_compiler_flag("-std=c++11" HAS_CPP11_FLAG)
25
26 if (HAS_CPP14_FLAG)
27 set(PYBIND11_CPP_STANDARD -std=c++14)
28 elseif (HAS_CPP11_FLAG)
29 set(PYBIND11_CPP_STANDARD -std=c++11)
30 else()
31 message(FATAL_ERROR "Unsupported compiler -- pybind11 requires C++11 support!")
32 endif()
33
34 set(PYBIND11_CPP_STANDARD ${PYBIND11_CPP_STANDARD} CACHE STRING
35 "C++ standard flag, e.g. -std=c++11 or -std=c++14. Defaults to latest available." FORCE)
36 endif()
37endfunction()
38
39# Checks whether the given CXX/linker flags can compile and link a cxx file. cxxflags and
40# linkerflags are lists of flags to use. The result variable is a unique variable name for each set
41# of flags: the compilation result will be cached base on the result variable. If the flags work,
42# sets them in cxxflags_out/linkerflags_out internal cache variables (in addition to ${result}).
43function(_pybind11_return_if_cxx_and_linker_flags_work result cxxflags linkerflags cxxflags_out linkerflags_out)
44 set(CMAKE_REQUIRED_LIBRARIES ${linkerflags})
45 check_cxx_compiler_flag("${cxxflags}" ${result})
46 if (${result})
47 set(${cxxflags_out} "${cxxflags}" CACHE INTERNAL "" FORCE)
48 set(${linkerflags_out} "${linkerflags}" CACHE INTERNAL "" FORCE)
49 endif()
50endfunction()
51
52# Internal: find the appropriate link time optimization flags for this compiler
53function(_pybind11_add_lto_flags target_name prefer_thin_lto)
54 if (NOT DEFINED PYBIND11_LTO_CXX_FLAGS)
55 set(PYBIND11_LTO_CXX_FLAGS "" CACHE INTERNAL "")
56 set(PYBIND11_LTO_LINKER_FLAGS "" CACHE INTERNAL "")
57
58 if(CMAKE_CXX_COMPILER_ID MATCHES "GNU|Clang")
59 set(cxx_append "")
60 set(linker_append "")
61 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND NOT APPLE)
62 # Clang Gold plugin does not support -Os; append -O3 to MinSizeRel builds to override it
63 set(linker_append ";$<$<CONFIG:MinSizeRel>:-O3>")
64 elseif(CMAKE_CXX_COMPILER_ID MATCHES "GNU")
65 set(cxx_append ";-fno-fat-lto-objects")
66 endif()
67
68 if (CMAKE_CXX_COMPILER_ID MATCHES "Clang" AND prefer_thin_lto)
69 _pybind11_return_if_cxx_and_linker_flags_work(HAS_FLTO_THIN
70 "-flto=thin${cxx_append}" "-flto=thin${linker_append}"
71 PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
72 endif()
73
74 if (NOT HAS_FLTO_THIN)
75 _pybind11_return_if_cxx_and_linker_flags_work(HAS_FLTO
76 "-flto${cxx_append}" "-flto${linker_append}"
77 PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
78 endif()
79 elseif (CMAKE_CXX_COMPILER_ID MATCHES "Intel")
80 # Intel equivalent to LTO is called IPO
81 _pybind11_return_if_cxx_and_linker_flags_work(HAS_INTEL_IPO
82 "-ipo" "-ipo" PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
83 elseif(MSVC)
84 # cmake only interprets libraries as linker flags when they start with a - (otherwise it
85 # converts /LTCG to \LTCG as if it was a Windows path). Luckily MSVC supports passing flags
86 # with - instead of /, even if it is a bit non-standard:
87 _pybind11_return_if_cxx_and_linker_flags_work(HAS_MSVC_GL_LTCG
88 "/GL" "-LTCG" PYBIND11_LTO_CXX_FLAGS PYBIND11_LTO_LINKER_FLAGS)
89 endif()
90
91 if (PYBIND11_LTO_CXX_FLAGS)
92 message(STATUS "LTO enabled")
93 else()
94 message(STATUS "LTO disabled (not supported by the compiler and/or linker)")
95 endif()
96 endif()
97
98 # Enable LTO flags if found, except for Debug builds
99 if (PYBIND11_LTO_CXX_FLAGS)
100 target_compile_options(${target_name} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:${PYBIND11_LTO_CXX_FLAGS}>")
101 endif()
102 if (PYBIND11_LTO_LINKER_FLAGS)
103 target_link_libraries(${target_name} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:${PYBIND11_LTO_LINKER_FLAGS}>")
104 endif()
105endfunction()
106
107# Build a Python extension module:
108# pybind11_add_module(<name> [MODULE | SHARED] [EXCLUDE_FROM_ALL]
109# [NO_EXTRAS] [THIN_LTO] source1 [source2 ...])
110#
111function(pybind11_add_module target_name)
112 set(options MODULE SHARED EXCLUDE_FROM_ALL NO_EXTRAS THIN_LTO)
113 cmake_parse_arguments(ARG "${options}" "" "" ${ARGN})
114
115 if(ARG_MODULE AND ARG_SHARED)
116 message(FATAL_ERROR "Can't be both MODULE and SHARED")
117 elseif(ARG_SHARED)
118 set(lib_type SHARED)
119 else()
120 set(lib_type MODULE)
121 endif()
122
123 if(ARG_EXCLUDE_FROM_ALL)
124 set(exclude_from_all EXCLUDE_FROM_ALL)
125 endif()
126
127 add_library(${target_name} ${lib_type} ${exclude_from_all} ${ARG_UNPARSED_ARGUMENTS})
128
129 target_include_directories(${target_name}
130 PRIVATE ${PYBIND11_INCLUDE_DIR} # from project CMakeLists.txt
131 PRIVATE ${pybind11_INCLUDE_DIR} # from pybind11Config
132 PRIVATE ${PYTHON_INCLUDE_DIRS})
133
134 # The prefix and extension are provided by FindPythonLibsNew.cmake
135 set_target_properties(${target_name} PROPERTIES PREFIX "${PYTHON_MODULE_PREFIX}")
136 set_target_properties(${target_name} PROPERTIES SUFFIX "${PYTHON_MODULE_EXTENSION}")
137
138 if(WIN32 OR CYGWIN)
139 # Link against the Python shared library on Windows
140 target_link_libraries(${target_name} PRIVATE ${PYTHON_LIBRARIES})
141 elseif(APPLE)
142 # It's quite common to have multiple copies of the same Python version
143 # installed on one's system. E.g.: one copy from the OS and another copy
144 # that's statically linked into an application like Blender or Maya.
145 # If we link our plugin library against the OS Python here and import it
146 # into Blender or Maya later on, this will cause segfaults when multiple
147 # conflicting Python instances are active at the same time (even when they
148 # are of the same version).
149
150 # Windows is not affected by this issue since it handles DLL imports
151 # differently. The solution for Linux and Mac OS is simple: we just don't
152 # link against the Python library. The resulting shared library will have
153 # missing symbols, but that's perfectly fine -- they will be resolved at
154 # import time.
155
156 target_link_libraries(${target_name} PRIVATE "-undefined dynamic_lookup")
157
158 if(ARG_SHARED)
159 # Suppress CMake >= 3.0 warning for shared libraries
160 set_target_properties(${target_name} PROPERTIES MACOSX_RPATH ON)
161 endif()
162 endif()
163
164 select_cxx_standard()
165 if(NOT MSVC)
166 # Make sure C++11/14 are enabled
167 target_compile_options(${target_name} PUBLIC ${PYBIND11_CPP_STANDARD})
168 endif()
169
170 if(ARG_NO_EXTRAS)
171 return()
172 endif()
173
174 _pybind11_add_lto_flags(${target_name} ${ARG_THIN_LTO})
175
176 if (NOT MSVC AND NOT ${CMAKE_BUILD_TYPE} MATCHES Debug)
177 # Set the default symbol visibility to hidden (very important to obtain small binaries)
178 target_compile_options(${target_name} PRIVATE "-fvisibility=hidden")
179
180 # Strip unnecessary sections of the binary on Linux/Mac OS
181 if(CMAKE_STRIP)
182 if(APPLE)
183 add_custom_command(TARGET ${target_name} POST_BUILD
184 COMMAND ${CMAKE_STRIP} -x $<TARGET_FILE:${target_name}>)
185 else()
186 add_custom_command(TARGET ${target_name} POST_BUILD
187 COMMAND ${CMAKE_STRIP} $<TARGET_FILE:${target_name}>)
188 endif()
189 endif()
190 endif()
191
192 if(MSVC)
193 # /MP enables multithreaded builds (relevant when there are many files), /bigobj is
194 # needed for bigger binding projects due to the limit to 64k addressable sections
195 target_compile_options(${target_name} PRIVATE /MP /bigobj)
196 endif()
197endfunction()