diff --git a/cygwin/GNUmakefile.in b/cygwin/GNUmakefile.in
index b13c3d9c8a..da00b8aa3c 100644
--- a/cygwin/GNUmakefile.in
+++ b/cygwin/GNUmakefile.in
@@ -89,6 +89,7 @@ MSYS2_ARG_CONV_EXCL_PARAM = --exclude=;--name=
 yes-test-ruby:	 export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 yes-test-all:	 export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 yes-test-almost: export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
+test/% spec/%/ spec/%_spec.rb: export MSYS2_ARG_CONV_EXCL=$(MSYS2_ARG_CONV_EXCL_PARAM)
 
 endif