CMake: Add an assert to DEAL_II_PACKAGE_HANDLE

diff --git a/cmake/macros/macro_deal_ii_package_handle.cmake b/cmake/macros/macro_deal_ii_package_handle.cmake
index 7ef56e5ae43350ebb4fa8427c24bda231265105d..3c8378454c4dab13aadffaa1f4de0672628c9bef 100644 (file)
--- a/cmake/macros/macro_deal_ii_package_handle.cmake
+++ b/cmake/macros/macro_deal_ii_package_handle.cmake
@@ -93,6 +93,13 @@ MACRO(DEAL_II_PACKAGE_HANDLE _feature)
       SET(_fill_clear TRUE)
 
     ELSE()
+      IF ("${_suffix}" STREQUAL "")
+        MESSAGE(FATAL_ERROR
+          "Internal configuration error: the second "
+          "argument to DEAL_II_PACKAGE_HANDLE must be a keyword"
+          )
+      ENDIF()
+
       MARK_AS_ADVANCED(${_arg})
 
       IF(_fill_clear) # FIXME