Merge pull request #213 from Steelskin/fabrice/cmake-install-paths

[cmake] Install libraries in standard directories

Author: glessard

CMakeLists.txt

@@ -11,6 +11,8 @@ cmake_minimum_required(VERSION 3.16.0)
 project(SwiftSystem
   LANGUAGES C Swift)
 
+include(GNUInstallDirs)
+
 list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/modules)
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)

cmake/modules/SwiftSupport.cmake

@@ -69,6 +69,28 @@ function(get_swift_host_os result_var_name)
   endif()
 endfunction()
 
+if(NOT Swift_MODULE_TRIPLE)
+  # Attempt to get the module triple from the Swift compiler.
+  set(module_triple_command "${CMAKE_Swift_COMPILER}" -print-target-info)
+  if(CMAKE_Swift_COMPILER_TARGET)
+    list(APPEND module_triple_command -target ${CMAKE_Swift_COMPILER_TARGET})
+  endif()
+  execute_process(COMMAND ${module_triple_command}
+    OUTPUT_VARIABLE target_info_json)
+  string(JSON module_triple GET "${target_info_json}" "target" "moduleTriple")
+
+  # Exit now if we failed to infer the triple.
+  if(NOT module_triple)
+    message(FATAL_ERROR
+      "Failed to get module triple from Swift compiler. "
+      "Compiler output: ${target_info_json}")
+  endif()
+
+  # Cache the module triple for future use.
+  set(Swift_MODULE_TRIPLE "${module_triple}" CACHE STRING "swift module triple used for installed swiftmodule and swiftinterface files")
+  mark_as_advanced(Swift_MODULE_TRIPLE)
+endif()
+
 function(_install_target module)
   get_swift_host_os(swift_os)
   get_target_property(type ${module} TYPE)
@@ -79,24 +101,20 @@ function(_install_target module)
     set(swift swift)
   endif()
 
-  install(TARGETS ${module}
-    ARCHIVE DESTINATION lib/${swift}/${swift_os}
-    LIBRARY DESTINATION lib/${swift}/${swift_os}
-    RUNTIME DESTINATION bin)
+  install(TARGETS ${module})
   if(type STREQUAL EXECUTABLE)
     return()
   endif()
 
-  get_swift_host_arch(swift_arch)
   get_target_property(module_name ${module} Swift_MODULE_NAME)
   if(NOT module_name)
     set(module_name ${module})
   endif()
 
   install(FILES $<TARGET_PROPERTY:${module},Swift_MODULE_DIRECTORY>/${module_name}.swiftdoc
-    DESTINATION lib/${swift}/${swift_os}/${module_name}.swiftmodule
-    RENAME ${swift_arch}.swiftdoc)
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/${swift}/${swift_os}/${module_name}.swiftmodule
+    RENAME ${Swift_MODULE_TRIPLE}.swiftdoc)
   install(FILES $<TARGET_PROPERTY:${module},Swift_MODULE_DIRECTORY>/${module_name}.swiftmodule
-    DESTINATION lib/${swift}/${swift_os}/${module_name}.swiftmodule
-    RENAME ${swift_arch}.swiftmodule)
+    DESTINATION ${CMAKE_INSTALL_LIBDIR}/${swift}/${swift_os}/${module_name}.swiftmodule
+    RENAME ${Swift_MODULE_TRIPLE}.swiftmodule)
 endfunction()