diff --git a/library/Makefile.common b/library/Makefile.common
index 6912530f7..8512a7552 100644
--- a/library/Makefile.common
+++ b/library/Makefile.common
@@ -20,7 +20,7 @@ all: $(OLEAN_FILES) $(DEP_FILES)
 	@rm -f $@.tmp.1
 	@rm -f $@.tmp.2
 
-include $(LEAN_FILES:.lean=.d)
+-include $(LEAN_FILES:.lean=.d)
 
 .PHONY: all clean
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 9da0e7bcc..f8fc99441 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -328,4 +328,9 @@ endif()
 add_custom_target(clean-olean
    WORKING_DIRECTORY ${LEAN_SOURCE_DIR}/../library
    COMMAND find . -name '*.olean' -exec rm -f '{}' '\;'
-)
\ No newline at end of file
+   )
+
+add_custom_target(clean-d
+  WORKING_DIRECTORY ${LEAN_SOURCE_DIR}/../library
+  COMMAND find . -name '*.d' -exec rm -f '{}' '\;'
+  )
\ No newline at end of file