diff --git a/sys/tools/makeobjops.awk b/sys/tools/makeobjops.awk
--- a/sys/tools/makeobjops.awk
+++ b/sys/tools/makeobjops.awk
@@ -466,6 +466,10 @@
 			debug("Included file: " incld);
 			printc("#include " incld);
 		}
+		else if (/^#[ 	]*if/ || /^#[   ]*else/ || /^#[   ]*endif/) {
+			printh($0);
+			printc($0);
+		}
 
 		sub(/#.*/, "");		# remove comments
 		sub(/^[	 ]+/, "");	# remove leading ...