diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index 2f11f8fab2..6573427db5 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -337,12 +337,7 @@ foreach(PKG ${DEFAULT_PACKAGES} ${OTHER_PACKAGES})
 
   foreach(PKG_FILE in ${${PKG}_SOURCES})
       get_filename_component(FNAME ${PKG_FILE} NAME)
-      list(FIND LIB_SOURCES ${LAMMPS_SOURCE_DIR}/${FNAME} IDX)
-
-      if(NOT (IDX LESS 0))
-          #message("Ignoring ${PKG_FILE}...")
-          list(REMOVE_AT LIB_SOURCES ${IDX})
-      endif()
+      list(REMOVE_ITEM LIB_SOURCES ${LAMMPS_SOURCE_DIR}/${FNAME})
   endforeach()
 
   foreach(PKG_FILE in ${${PKG}_HEADERS})
diff --git a/cmake/Modules/StyleHeaderUtils.cmake b/cmake/Modules/StyleHeaderUtils.cmake
index c3433c42ce..32054c53ba 100644
--- a/cmake/Modules/StyleHeaderUtils.cmake
+++ b/cmake/Modules/StyleHeaderUtils.cmake
@@ -87,13 +87,8 @@ endfunction(RegisterStyles)
 
 function(RemovePackageHeader headers pkg_header)
     get_property(hlist GLOBAL PROPERTY ${headers})
-
-    list(FIND hlist ${pkg_header} idx)
-    if(NOT (idx LESS 0))
-      list(REMOVE_AT hlist ${idx})
-      #message("Ignoring ${pkg_header}...")
-      set_property(GLOBAL PROPERTY ${headers} "${hlist}")
-    endif()
+    list(REMOVE_ITEM hlist ${pkg_header})
+    set_property(GLOBAL PROPERTY ${headers} "${hlist}")
 endfunction(RemovePackageHeader)
 
 function(DetectAndRemovePackageHeader fname)