don't prepend "$(srcdir)/" to paths beginning with "$" since they are likely
to be absolute.
diff --git a/Modules/makesetup b/Modules/makesetup
index 18fb682..e8229e6 100755
--- a/Modules/makesetup
+++ b/Modules/makesetup
@@ -189,6 +189,7 @@
 			case $src in
 			glmodule.c) ;;
 			/*) ;;
+			\$*) ;;
 			*) src='$(srcdir)/'$src;;
 			esac
 			case $doconfig in