build: use modern target property handling

Use specific operations for setting the compile flags, link flags,
linked libraries, and library search paths.  This allows us to use CMake
more effectively, simplifies the logic, and will ensure that flags are
not duplicated.

Author: compnerd

cmake/modules/AddSwift.cmake

@@ -702,14 +702,6 @@ function(_add_swift_lipo_target)
   endif()
 endfunction()
 
-function(swift_target_link_search_directories target directories)
-  set(STLD_FLAGS "")
-  foreach(directory ${directories})
-    set(STLD_FLAGS "${STLD_FLAGS} \"${CMAKE_LIBRARY_PATH_FLAG}${directory}\"")
-  endforeach()
-  set_property(TARGET ${target} APPEND_STRING PROPERTY LINK_FLAGS ${STLD_FLAGS})
-endfunction()
-
 # Add a single variant of a new Swift library.
 #
 # Usage:
@@ -886,22 +878,10 @@ function(_add_swift_library_single target name)
   if(SWIFT_EMBED_BITCODE_SECTION AND NOT SWIFTLIB_SINGLE_DONT_EMBED_BITCODE)
     if("${SWIFTLIB_SINGLE_SDK}" STREQUAL "IOS" OR "${SWIFTLIB_SINGLE_SDK}" STREQUAL "TVOS" OR "${SWIFTLIB_SINGLE_SDK}" STREQUAL "WATCHOS")
       list(APPEND SWIFTLIB_SINGLE_C_COMPILE_FLAGS "-fembed-bitcode")
-      list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-bitcode_bundle" "-Xlinker" "-lto_library" "-Xlinker" "${LLVM_LIBRARY_DIR}/libLTO.dylib")
-      # If we are asked to hide symbols, pass the obfuscation flag to libLTO.
-      if (SWIFT_EMBED_BITCODE_SECTION_HIDE_SYMBOLS)
-        list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-bitcode_hide_symbols")
-      endif()
       set(embed_bitcode_arg EMBED_BITCODE)
     endif()
   endif()
 
-  if(${SWIFTLIB_SINGLE_SDK} IN_LIST SWIFT_APPLE_PLATFORMS)
-    list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-compatibility_version" "-Xlinker" "1")
-    if (SWIFT_COMPILER_VERSION)
-      list(APPEND SWIFTLIB_SINGLE_LINK_FLAGS "-Xlinker" "-current_version" "-Xlinker" "${SWIFT_COMPILER_VERSION}" )
-    endif()
-  endif()
-
   if(XCODE)
     string(REGEX MATCHALL "/[^/]+" split_path ${CMAKE_CURRENT_SOURCE_DIR})
     list(GET split_path -1 dir)
@@ -1450,17 +1430,32 @@ function(_add_swift_library_single target name)
     set(PLIST_INFO_BUILD_VERSION)
   endif()
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
   # Set compilation and link flags.
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags}")
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET "${target}" APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
-  swift_target_link_search_directories("${target}" "${library_search_directories}")
+  target_compile_options(${target} PRIVATE
+    ${c_compile_flags})
+  target_link_options(${target} PRIVATE
+    ${link_flags})
+  if(${SWIFTLIB_SINGLE_SDK} IN_LIST SWIFT_APPLE_PLATFORMS)
+    target_link_options(${target} PRIVATE
+      "LINKER:-compatibility_version,1")
+    if(SWIFT_COMPILER_VERSION)
+      target_link_options(${target} PRIVATE
+        "LINKER:-current_version,${SWIFT_COMPILER_VERSION}")
+    endif()
+    # Include LLVM Bitcode slices for iOS, Watch OS, and Apple TV OS device libraries.
+    if(SWIFT_EMBED_BITCODE_SECTION AND NOT SWIFTLIB_SINGLE_DONT_EMBED_BITCODE)
+      if(${SWIFTLIB_SINGLE_SDK} MATCHES "(I|TV|WATCH)OS")
+        target_link_options(${target} PRIVATE
+          "LINKER:-bitcode_bundle"
+          $<$<BOOL:SWIFT_EMBED_BITCODE_SECTION_HIDE_SYMBOLS>:"LINKER:-bitcode_hide_symbols">
+          "LINKER:-lto_library,${LLVM_LIBRARY_DIR}/libLTO.dylib")
+      endif()
+    endif()
+  endif()
+  target_link_libraries(${target} PRIVATE
+    ${link_libraries})
+  target_link_directories(${target} PRIVATE
+    ${library_search_directories})
 
   # Adjust the linked libraries for windows targets.  On Windows, the link is
   # performed against the import library, and the runtime uses the dll.  Not
@@ -1510,8 +1505,8 @@ function(_add_swift_library_single target name)
   endif()
 
   if(target_static)
-    set_property(TARGET "${target_static}" APPEND_STRING PROPERTY
-        COMPILE_FLAGS " ${c_compile_flags}")
+    target_link_options(${target_static} PRIVATE
+      ${c_compile_flags})
     # FIXME: The fallback paths here are going to be dynamic libraries.
 
     if(SWIFTLIB_INSTALL_WITH_SHARED)
@@ -1523,7 +1518,8 @@ function(_add_swift_library_single target name)
         "${search_base_dir}/${SWIFTLIB_SINGLE_SUBDIR}"
         "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/../lib/swift/${SWIFTLIB_SINGLE_SUBDIR}"
         "${SWIFT_NATIVE_SWIFT_TOOLS_PATH}/../lib/swift/${SWIFT_SDK_${SWIFTLIB_SINGLE_SDK}_LIB_SUBDIR}")
-    swift_target_link_search_directories("${target_static}" "${library_search_directories}")
+    target_link_directories(${target_static} PRIVATE
+      ${library_search_directories})
     target_link_libraries("${target_static}" PRIVATE
         ${SWIFTLIB_SINGLE_PRIVATE_LINK_LIBRARIES})
   endif()
@@ -2624,16 +2620,14 @@ function(_add_swift_executable_single name)
         ${SWIFTEXE_SINGLE_DEPENDS})
   llvm_update_compile_flags("${name}")
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
-  set_property(TARGET ${name} APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags}")
-  swift_target_link_search_directories("${name}" "${library_search_directories}")
-  set_property(TARGET ${name} APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET ${name} APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
+  target_compile_options(${name} PRIVATE
+    ${c_compile_flags})
+  target_link_directories(${name} PRIVATE
+    ${library_search_directories})
+  target_link_options(${name} PRIVATE
+    ${link_flags})
+  target_link_libraries(${name} PRIVATE
+    ${link_libraries})
   if (SWIFT_PARALLEL_LINK_JOBS)
     set_property(TARGET ${name} PROPERTY JOB_POOL_LINK swift_link_job_pool)
   endif()

cmake/modules/SwiftList.cmake

@@ -38,15 +38,6 @@ function(_list_add_string_suffix input_list suffix result_var_name)
   set("${result_var_name}" "${result}" PARENT_SCOPE)
 endfunction()
 
-function(_list_escape_for_shell input_list result_var_name)
-  set(result "")
-  foreach(element ${input_list})
-    string(REPLACE " " "\\ " element "${element}")
-    set(result "${result}${element} ")
-  endforeach()
-  set("${result_var_name}" "${result}" PARENT_SCOPE)
-endfunction()
-
 function(list_replace input_list old new)
   set(replaced_list)
   foreach(item ${${input_list}})

lib/SymbolGraphGen/CMakeLists.txt

@@ -7,7 +7,7 @@ add_swift_host_library(swiftSymbolGraphGen STATIC
   SymbolGraphGen.cpp
   SymbolGraphASTWalker.cpp)
 
-target_link_libraries(swiftSymbolGraphGen
+target_link_libraries(swiftSymbolGraphGen PRIVATE
   swiftAST
   swiftFrontend
   swiftMarkup)

tools/SourceKit/cmake/modules/AddSwiftSourceKit.cmake

@@ -70,17 +70,15 @@ function(add_sourcekit_default_compiler_flags target)
     LINK_LIBRARIES_VAR_NAME link_libraries
     LIBRARY_SEARCH_DIRECTORIES_VAR_NAME library_search_directories)
 
-  # Convert variables to space-separated strings.
-  _list_escape_for_shell("${c_compile_flags}" c_compile_flags)
-  _list_escape_for_shell("${link_flags}" link_flags)
-
   # Set compilation and link flags.
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      COMPILE_FLAGS " ${c_compile_flags} -fblocks")
-  set_property(TARGET "${target}" APPEND_STRING PROPERTY
-      LINK_FLAGS " ${link_flags}")
-  set_property(TARGET "${target}" APPEND PROPERTY LINK_LIBRARIES ${link_libraries})
-  swift_target_link_search_directories("${target}" "${library_search_directories}")
+  target_compile_options(${target} PRIVATE
+    -fblocks)
+  target_link_options(${target} PRIVATE
+    ${link_flags})
+  target_link_directories(${target} PRIVATE
+    ${library_search_directories})
+  target_link_libraries(${target} PRIVATE
+    ${link_libraries})
 endfunction()
 
 # Add a new SourceKit library.