[build] Merge Clang's features.json from binary directory, handle values

Author: jansvoboda11

lib/Option/CMakeLists.txt

@@ -8,7 +8,7 @@ target_link_libraries(swiftOption PRIVATE
 
 set(features_merger "${SWIFT_SOURCE_DIR}/utils/merge-features.py")
 set(features_file_swift_src "${CMAKE_CURRENT_SOURCE_DIR}/features.json")
-set(features_file_clang_src "${LLVM_MAIN_SRC_DIR}/../clang/tools/driver/features.json")
+set(features_file_clang_src "${LLVM_BINARY_DIR}/share/clang/features.json")
 set(features_file_dest "${CMAKE_BINARY_DIR}/share/swift/features.json")
 
 add_custom_command(

utils/merge-features.py

@@ -52,7 +52,12 @@ def read_features(from_file, add_prefix):
         if "name" not in feature:
             invalid_file(from_file, "missing name in features list")
 
-        features.append({"name": add_prefix + feature["name"]})
+        new_feature = {"name": add_prefix + feature["name"]}
+
+        if "value" in feature:
+            new_feature.update({"value" : feature["value"]})
+
+        features.append(new_feature)
     return features