Filter .generated in trailing whitespace check due to trailing whitespaces in DMD

Author: wilzbach

posix.mak

@@ -641,7 +641,7 @@ $(PHOBOS_STABLE_FILES_GENERATED): $(PHOBOS_STABLE_DIR_GENERATED)/%: $(PHOBOS_STA
 
 test: $(ASSERT_WRITELN_BIN)_test all
 	@echo "Searching for trailing whitespace"
-	@grep -n '[[:blank:]]$$' $$(find . -type f -name "*.dd") ; test $$? -eq 1
+	@grep -n '[[:blank:]]$$' $$(find . -type f -name "*.dd" | grep -v .generated) ; test $$? -eq 1
 	@echo "Searching for undefined macros"
 	@grep -n "UNDEFINED MACRO" $$(find $(DOC_OUTPUT_DIR) -type f -name "*.html" -not -path "$(DOC_OUTPUT_DIR)/phobos/*") ; test $$? -eq 1
 	@echo "Searching for undefined ddoc"