diff --git a/CMLibFormatSources.cmake b/CMLibFormatSources.cmake
index 6c4a3c0..daf5e09 100644
--- a/CMLibFormatSources.cmake
+++ b/CMLibFormatSources.cmake
@@ -4,20 +4,26 @@ function(add_format_sources target)
   if(NOT TARGET format-sources)
     add_custom_target(format-sources)
   endif()
+  if(NOT TARGET check-format-sources)
+    add_custom_target(check-format-sources)
+  endif()
   if(NOT TARGET doc-add-comments)
     add_custom_target(doc-add-comments)
   endif()
 
   find_program(UNCRUSTIFY_EXE NAMES uncrustify)
   if(UNCRUSTIFY_EXE)
-    list(APPEND UNCRUSTIFY_OPTS --replace --no-backup)
     if(EXISTS ${CMAKE_SOURCE_DIR}/cmake/etc/uncrustify/default.cfg)
       list(APPEND UNCRUSTIFY_OPTS -c ${CMAKE_SOURCE_DIR}/cmake/etc/uncrustify/default.cfg)
     endif()
     # cmake-format: off
-    add_custom_target(format-sources-uncrustify-${target} COMMAND ${UNCRUSTIFY_EXE} ${UNCRUSTIFY_OPTS}
-      --mtime ${_sources})
-    add_custom_target(doc-add-comments-uncrustify-${target} COMMAND ${UNCRUSTIFY_EXE} ${UNCRUSTIFY_OPTS}
+    add_custom_target(check-format-sources-uncrustify-${target} COMMAND ${UNCRUSTIFY_EXE}
+      ${UNCRUSTIFY_OPTS} --check ${_sources})
+    list(APPEND UNCRUSTIFY_OPTS --replace --no-backup)
+    add_custom_target(format-sources-uncrustify-${target} COMMAND ${UNCRUSTIFY_EXE}
+      ${UNCRUSTIFY_OPTS} --mtime ${_sources})
+    add_custom_target(doc-add-comments-uncrustify-${target} COMMAND ${UNCRUSTIFY_EXE}
+      ${UNCRUSTIFY_OPTS}
       --set cmt_insert_file_header=fileheader.txt
       --set cmt_insert_file_footer=filefooter.txt
       --set cmt_insert_func_header=funcheader.txt
@@ -25,6 +31,7 @@ function(add_format_sources target)
       --set cmt_insert_before_ctor_dtor=true ${_sources})
     # cmake-format: on
     add_dependencies(format-sources format-sources-uncrustify-${target})
+    add_dependencies(check-format-sources check-format-sources-uncrustify-${target})
     add_dependencies(doc-add-comments doc-add-comments-uncrustify-${target})
   else()
     message(STATUS "CMLIB warning:")