[CMake] Stop using globs on the apinotes directory.

The problem here is that there isn't an obvious way to force a CMake
reconfiguration when you need to add new apinotes. This dates back to
when we (internally) had the apinotes in a separate repo, but that
hasn't been the case for a long time.

We're still not using a /normal/ CMake add_subdirectory for these
because we compile the apinotes as part of building overlays for
frameworks that have both overlays and apinotes, and I didn't want to
touch any of that stuff right now.

Author: jrose-apple

CMakeLists.txt

@@ -771,21 +771,17 @@ endif()
 #
 # Set up global CMake variables for API notes.
 #
-# API notes version 1.0.0
-#
-# Change the above comment to 'touch' this file and keep incremental builds
-# working when adding a new apinotes file.
-#
 set(SWIFT_API_NOTES_PATH "${SWIFT_SOURCE_DIR}/apinotes")
-if(NOT EXISTS "${SWIFT_API_NOTES_PATH}/Foundation.apinotes")
+include("${SWIFT_API_NOTES_PATH}/CMakeLists.txt")
+if(NOT DEFINED SWIFT_API_NOTES_INPUTS)
   message(FATAL_ERROR "API notes are not available in ${SWIFT_API_NOTES_PATH}")
 endif()
-
-file(GLOB SWIFT_API_NOTES_INPUT_FILES "${SWIFT_API_NOTES_PATH}/*.apinotes")
-foreach(file ${SWIFT_API_NOTES_INPUT_FILES})
-  get_filename_component(name "${file}" NAME_WE)
-  list(APPEND SWIFT_API_NOTES_INPUTS ${name})
-endforeach()
+#
+# file(GLOB SWIFT_API_NOTES_INPUT_FILES "${SWIFT_API_NOTES_PATH}/*.apinotes")
+# foreach(file ${SWIFT_API_NOTES_INPUT_FILES})
+#   get_filename_component(name "${file}" NAME_WE)
+#   list(APPEND SWIFT_API_NOTES_INPUTS ${name})
+# endforeach()
 
 # Add all of the subdirectories, where we actually do work.
 if(SWIFT_BUILD_TOOLS)

apinotes/CMakeLists.txt

@@ -0,0 +1,37 @@
+set(SWIFT_API_NOTES_INPUTS
+  AppKit
+  AVFoundation
+  CoreData
+  CoreGraphics
+  CoreLocation
+  Dispatch
+  Foundation
+  GameKit
+  HomeKit
+  NotificationCenter
+  ObjectiveC
+  SpriteKit
+  TVMLKit
+  TVServices
+  UIKit
+  WatchKit
+  WebKit)
+
+if(NOT DEFINED SWIFT_API_NOTES_PATH)
+  message(FATAL_ERROR "Define SWIFT_API_NOTES_PATH before including this file")
+endif()
+
+foreach(module ${SWIFT_API_NOTES_INPUTS})
+  if(NOT EXISTS "${SWIFT_API_NOTES_PATH}/${module}.apinotes")
+    message(SEND_ERROR "Missing apinotes for ${module}")
+  endif()
+endforeach()
+
+file(GLOB SWIFT_API_NOTES_INPUT_FILES "${SWIFT_API_NOTES_PATH}/*.apinotes")
+foreach(file ${SWIFT_API_NOTES_INPUT_FILES})
+  get_filename_component(name "${file}" NAME_WE)
+  list(FIND SWIFT_API_NOTES_INPUTS "${name}" name_index)
+  if(name_index EQUAL -1)
+    message(WARNING "Found apinotes for ${name}; please add to CMakeLists.txt")
+  endif()
+endforeach()

apinotes/README.md

@@ -70,9 +70,8 @@ xcrun swift -apinotes -yaml-to-binary -target x64_64-apple-ios7.0 -o $SWIFT_EXEC
 ```
 
 To add API notes for a system module `$MODULE` that does not have them yet,
-create a new source file `$MODULE.apinotes`. Newly-added API notes will require
-re-running CMake. Updated API notes will be found by the build system during
-the next build.
+create a new source file `$MODULE.apinotes` and update CMakeLists.txt.
+Updated API notes will be found by the build system during the next build.
 
 Note that Swift provides decompilation of binary API notes files via
 the `-apinotes -binary-to-yaml` option, which allows one to inspect