diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,12 +29,27 @@
 set(REQUIRED_QT_VERSION 5.7.0)
 find_package(Qt5 ${REQUIRED_QT_VERSION} CONFIG REQUIRED Core)
 
+# TODO: create ECM macro for automoc & json things
 set(KCoreAddons_AUTOMOC_MACRO_NAMES "K_PLUGIN_FACTORY_WITH_JSON" "K_PLUGIN_FACTORY" "K_PLUGIN_CLASS_WITH_JSON")
 if(NOT CMAKE_VERSION VERSION_LESS "3.10.0")
   # CMake 3.9+ warns about automoc on files without Q_OBJECT, and doesn't know about other macros.
   # 3.10+ lets us provide more macro names that require automoc.
   list(APPEND CMAKE_AUTOMOC_MACRO_NAMES ${KCoreAddons_AUTOMOC_MACRO_NAMES})
 endif()
+set(KCoreAddons_AUTOMOC_MACRO_NAMES_WITH_JSON_ARG2 "K_PLUGIN_FACTORY_WITH_JSON" "K_PLUGIN_CLASS_WITH_JSON")
+if(NOT CMAKE_VERSION VERSION_LESS "3.9.0")
+    # CMake's automoc needs help to find names of plugin metadata files in case Q_PLUGIN_METADATA
+    # is indirectly used via other C++ preprocessor macros
+    # 3.9+ lets us provide some filter rule pairs (keyword, regexp) to match the names of such files
+    # in the plain text of the sources. See AUTOMOC_DEPEND_FILTERS docs for details.
+    foreach(macro_name  ${KCoreAddons_AUTOMOC_MACRO_NAMES_WITH_JSON_ARG2})
+        list(APPEND CMAKE_AUTOMOC_DEPEND_FILTERS
+            "${macro_name}"
+            "[\n^][ \t]*${macro_name}[ \t\n]*\\([^,]*,[ \t\n]*\"([^\"]+)\""
+        )
+    endforeach()
+endif()
+
 
 find_package(Threads)
 
diff --git a/KF5CoreAddonsConfig.cmake.in b/KF5CoreAddonsConfig.cmake.in
--- a/KF5CoreAddonsConfig.cmake.in
+++ b/KF5CoreAddonsConfig.cmake.in
@@ -9,6 +9,15 @@
   # 3.10+ lets us provide more macro names that require automoc.
   list(APPEND CMAKE_AUTOMOC_MACRO_NAMES @KCoreAddons_AUTOMOC_MACRO_NAMES@)
 endif()
+if(NOT CMAKE_VERSION VERSION_LESS "3.9.0")
+    foreach(macro_name  @KCoreAddons_AUTOMOC_MACRO_NAMES_WITH_JSON_ARG2@)
+        # tell automoc how to find names of plugin metadata files
+        list(APPEND CMAKE_AUTOMOC_DEPEND_FILTERS
+            "${macro_name}"
+            "[\n^][ \t]*${macro_name}[ \t\n]*\\([^,]*,[ \t\n]*\"([^\"]+)\""
+        )
+    endforeach()
+endif()
 
 if(CMAKE_CROSSCOMPILING AND KF5_HOST_TOOLING)
     find_file(TARGETSFILE KF5CoreAddons/KF5CoreAddonsToolingTargets.cmake