added a few more comments to the CMake build system
diff --git a/CMakeLists.txt b/CMakeLists.txt
index a0ceccf..f8f8a7b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,22 +9,28 @@
project(pybind)
+# Add a CMake parameter for choosing a desired Python version
+set(PYBIND_PYTHON_VERSION "" CACHE STRING "Python version to use for compiling the example application")
+
+# Set a default build configuration if none is specified. 'MinSizeRel' produces the smallest binaries
if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
message(STATUS "Setting build type to 'MinSizeRel' as none was specified.")
set(CMAKE_BUILD_TYPE MinSizeRel CACHE STRING "Choose the type of build." FORCE)
set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release"
"MinSizeRel" "RelWithDebInfo")
endif()
-
-set(PYBIND_PYTHON_VERSION "" CACHE STRING "Python version to use for compiling the example application")
+string(TOUPPER "${CMAKE_BUILD_TYPE}" U_CMAKE_BUILD_TYPE)
set(Python_ADDITIONAL_VERSIONS 3.4 3.5 3.6)
find_package(PythonLibs ${PYBIND_PYTHON_VERSION} REQUIRED)
find_package(PythonInterp ${PYBIND_PYTHON_VERSION} REQUIRED)
-string(TOUPPER "${CMAKE_BUILD_TYPE}" U_CMAKE_BUILD_TYPE)
if (UNIX)
+ # Enable C++11 mode
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
+
+ # Enable link time optimization and set the default symbol
+ # visibility to hidden (very important to obtain small binaries)
if (NOT ${U_CMAKE_BUILD_TYPE} MATCHES DEBUG)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fvisibility=hidden -flto")
endif()
@@ -41,8 +47,13 @@
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wextra")
endif()
-include_directories(${PYTHON_INCLUDE_DIR} include)
+# Include path for Python header files
+include_directories(${PYTHON_INCLUDE_DIR})
+# Include path for pybind11 header files
+include_directories(include)
+
+# Create the binding library
add_library(example SHARED
include/pybind/cast.h
include/pybind/common.h
@@ -66,14 +77,18 @@
example/example12.cpp
)
+# Don't add a 'lib' prefix to the shared library
set_target_properties(example PROPERTIES PREFIX "")
+
+# Write the output file directly into the 'example' directory
set_target_properties(example PROPERTIES LIBRARY_OUTPUT_DIRECTORY ${PROJECT_SOURCE_DIR}/example)
if (WIN32)
if (MSVC)
- # Enforce size-based optimization and link time code generation on MSVC (~30% smaller binaries in experiments)
- # /bigobj is needed for bigger binding projects due to the limit to 64k addressable sections
- # /MP enables multithreaded builds
+ # Enforce size-based optimization and link time code generation
+ # on MSVC (~30% smaller binaries in experiments). /bigobj is needed
+ # for bigger binding projects due to the limit to 64k addressable sections
+ # /MP enables multithreaded builds (relevant when there are many files).
set_target_properties(example PROPERTIES COMPILE_FLAGS "/Os /GL /MP /bigobj")
set_target_properties(example PROPERTIES LINK_FLAGS "/LTCG")
endif()
@@ -91,10 +106,11 @@
# into Blender or Maya later on, this will cause segfaults when multiple
# conflicting Python instances are active at the same time.
- # Windows does not seem to be affected by this issue. 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.
+ # 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")