[Python] Restructure Python libraries to not require system links

Author: guitargeek

bindings/pyroot/cppyy/CPyCppyy/CMakeLists.txt

@@ -15,61 +15,84 @@ set(headers
 
 set(sources
     src/API.cxx
-    src/CallContext.cxx
-    src/Converters.cxx
     src/CPPClassMethod.cxx
     src/CPPConstructor.cxx
     src/CPPDataMember.cxx
     src/CPPEnum.cxx
     src/CPPExcInstance.cxx
     src/CPPFunction.cxx
+    src/CPPGetSetItem.cxx
     src/CPPInstance.cxx
     src/CPPMethod.cxx
     src/CPPOperator.cxx
     src/CPPOverload.cxx
     src/CPPScope.cxx
-    src/CPPGetSetItem.cxx
-    src/CPyCppyyModule.cxx
+    src/CallContext.cxx
+    src/Converters.cxx
     src/CustomPyTypes.cxx
-    src/Dispatcher.cxx
     src/DispatchPtr.cxx
+    src/Dispatcher.cxx
     src/Executors.cxx
+    src/Initialization.cxx
     src/LowLevelViews.cxx
     src/MemoryRegulator.cxx
     src/ProxyWrappers.cxx
+    src/PyException.cxx
+    src/PyResult.cxx
     src/PyStrings.cxx
     src/Pythonize.cxx
     src/TemplateProxy.cxx
-    src/PyException.cxx
-    src/PyResult.cxx
     src/TupleOfInstances.cxx
     src/TypeManip.cxx
     src/Utility.cxx
 )
 
-file(RELATIVE_PATH PYTHONDIR_TO_LIBDIR "${CMAKE_INSTALL_FULL_PYTHONDIR}" "${CMAKE_INSTALL_FULL_LIBDIR}")
 
-set(libname cppyy)
+add_library(CPyCppyy SHARED ${headers} ${sources})
+# Set the suffix to '.so' and the prefix to 'lib'
+set_target_properties(CPyCppyy PROPERTIES  ${ROOT_LIBRARY_PROPERTIES})
+target_link_libraries(CPyCppyy PRIVATE Core)
+if(MSVC)
+  target_link_libraries(CPyCppyy PRIVATE cppyy_backend Python3::Python)
+  set_target_properties(CPyCppyy PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS TRUE)
+  set_target_properties(CPyCppyy PROPERTIES PREFIX "lib")
+  set_target_properties(CPyCppyy PROPERTIES SUFFIX ".pyd")
+elseif(APPLE)
+  target_link_libraries(CPyCppyy PRIVATE -Wl,-bind_at_load -Wl,-w -Wl,-undefined -Wl,dynamic_lookup cppyy_backend)
+else()
+  target_link_libraries(CPyCppyy PRIVATE -Wl,--unresolved-symbols=ignore-all cppyy_backend)
+endif()
 
-add_library(${libname} SHARED ${headers} ${sources})
+if(NOT MSVC)
+  target_compile_options(CPyCppyy PRIVATE -Wno-strict-aliasing)
+endif()
+if(NOT "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND NOT MSVC)
+  target_compile_options(CPyCppyy PRIVATE
+    -Wno-unused-but-set-parameter)
+endif()
+
+
+add_library(cppyy SHARED
+    src/CPyCppyyModule.cxx
+)
 # Set the suffix to '.so' and the prefix to 'lib'
-set_target_properties(${libname} PROPERTIES  ${ROOT_LIBRARY_PROPERTIES})
+set_target_properties(cppyy PROPERTIES  ${ROOT_LIBRARY_PROPERTIES})
 if(MSVC)
-  target_link_libraries(${libname} PUBLIC cppyy_backend Python3::Python)
-  set_target_properties(${libname} PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS TRUE)
-  set_target_properties(${libname} PROPERTIES PREFIX "lib")
-  set_target_properties(${libname} PROPERTIES SUFFIX ".pyd")
+  target_link_libraries(cppyy PRIVATE CPyCppyy)
+  set_target_properties(cppyy PROPERTIES WINDOWS_EXPORT_ALL_SYMBOLS TRUE)
+  set_target_properties(cppyy PROPERTIES PREFIX "lib")
+  set_target_properties(cppyy PROPERTIES SUFFIX ".pyd")
 elseif(APPLE)
-  target_link_libraries(${libname} PUBLIC -Wl,-bind_at_load -Wl,-w -Wl,-undefined -Wl,dynamic_lookup cppyy_backend)
+  target_link_libraries(cppyy PRIVATE -Wl,-bind_at_load -Wl,-w -Wl,-undefined -Wl,dynamic_lookup CPyCppyy)
 else()
-  target_link_libraries(${libname} PUBLIC -Wl,--unresolved-symbols=ignore-all cppyy_backend)
+  target_link_libraries(cppyy PRIVATE -Wl,--unresolved-symbols=ignore-all CPyCppyy)
 endif()
 
 if(NOT MSVC)
-  target_compile_options(${libname} PRIVATE -Wno-strict-aliasing)
+  target_compile_options(cppyy PRIVATE -Wno-strict-aliasing)
 endif()
 if(NOT "${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang" AND NOT MSVC)
-  target_compile_options(${libname} PRIVATE
+  target_compile_options(cppyy PRIVATE
     -Wno-unused-but-set-parameter)
 endif()
 
@@ -79,42 +102,61 @@ endif()
 # CPython docs for C/C++ extensions. see
 # https://docs.python.org/3/extending/extending.html#keyword-parameters-for-extension-functions
 if(CMAKE_CXX_COMPILER_ID STREQUAL "GNU" OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
-  target_compile_options(${libname} PRIVATE -Wno-cast-function-type)
+  target_compile_options(cppyy PRIVATE -Wno-cast-function-type)
+  target_compile_options(CPyCppyy PRIVATE -Wno-cast-function-type)
 endif()
 
 # Disables warnings in Python 3.8 caused by the temporary extra filed for tp_print compatibility
 # (see https://github.com/python/cpython/blob/3.8/Include/cpython/object.h#L260).
 # Note that Python 3.8 is the lowers Python version that is still supported by
 # ROOT, so this compile option can be completely removed soon.
 if(NOT MSVC AND Python3_VERSION VERSION_LESS 3.9)
-  target_compile_options(${libname} PRIVATE -Wno-missing-field-initializers)
+  target_compile_options(cppyy PRIVATE -Wno-missing-field-initializers)
+  target_compile_options(CPyCppyy PRIVATE -Wno-missing-field-initializers)
 endif()
 
-target_compile_definitions(${libname} PRIVATE NO_CPPYY_LEGACY_NAMESPACE)
+target_compile_definitions(CPyCppyy PRIVATE NO_CPPYY_LEGACY_NAMESPACE)
 
-target_include_directories(${libname}
-    SYSTEM PUBLIC ${Python3_INCLUDE_DIRS})
+target_include_directories(CPyCppyy SYSTEM PUBLIC ${Python3_INCLUDE_DIRS})
 
-target_include_directories(${libname}
-    PRIVATE
-      ${CMAKE_BINARY_DIR}/ginclude
+target_include_directories(CPyCppyy
     PUBLIC
       $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
 )
 
-set_property(GLOBAL APPEND PROPERTY ROOT_EXPORTED_TARGETS ${libname})
+if(NOT MSVC)
+  # Make sure that relative RUNPATH to main ROOT libraries is always correct.
+
+  file(RELATIVE_PATH pymoduledir_to_libdir_build ${localruntimedir} "${localruntimedir}")
+  file(RELATIVE_PATH pymoduledir_to_libdir_install ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_PYTHONDIR} "${CMAKE_INSTALL_FULL_LIBDIR}")
+
+  if(APPLE)
+    set_target_properties(cppyy PROPERTIES
+        BUILD_RPATH "@loader_path/${pymoduledir_to_libdir_build}"
+        INSTALL_RPATH "@loader_path/${pymoduledir_to_libdir_install}"
+    )
+  else()
+    set_target_properties(cppyy PROPERTIES
+        BUILD_RPATH "$ORIGIN/${pymoduledir_to_libdir_build}"
+        INSTALL_RPATH "$ORIGIN/${pymoduledir_to_libdir_install}"
+    )
+  endif()
+
+endif()
+
+set_property(GLOBAL APPEND PROPERTY ROOT_EXPORTED_TARGETS CPyCppyy)
+set_property(GLOBAL APPEND PROPERTY ROOT_EXPORTED_TARGETS cppyy)
 
 # Install library
-install(TARGETS ${libname} EXPORT ${CMAKE_PROJECT_NAME}Exports
+install(TARGETS CPyCppyy EXPORT ${CMAKE_PROJECT_NAME}Exports
                             RUNTIME DESTINATION ${CMAKE_INSTALL_BINDIR} COMPONENT libraries
                             LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR} COMPONENT libraries
                             ARCHIVE DESTINATION ${CMAKE_INSTALL_LIBDIR} COMPONENT libraries)
-if (NOT MSVC AND NOT CMAKE_INSTALL_LIBDIR STREQUAL CMAKE_INSTALL_PYTHONDIR)
-  # add a symlink to ${libname} in CMAKE_INSTALL_PYTHONDIR
-  set(LIB_FILE_NAME ${CMAKE_SHARED_LIBRARY_PREFIX}${libname}.so)
-  install(CODE "file(CREATE_LINK ${PYTHONDIR_TO_LIBDIR}/${LIB_FILE_NAME}
-    \$ENV{DESTDIR}${CMAKE_INSTALL_FULL_PYTHONDIR}/${LIB_FILE_NAME} SYMBOLIC)")
-endif()
+
+install(TARGETS cppyy EXPORT ${CMAKE_PROJECT_NAME}Exports
+                            RUNTIME DESTINATION ${CMAKE_INSTALL_PYTHONDIR} COMPONENT libraries
+                            LIBRARY DESTINATION ${CMAKE_INSTALL_PYTHONDIR} COMPONENT libraries
+                            ARCHIVE DESTINATION ${CMAKE_INSTALL_PYTHONDIR} COMPONENT libraries)
 
 file(COPY ${headers} DESTINATION ${CMAKE_BINARY_DIR}/include/CPyCppyy)
 install(FILES ${headers}