diff --git a/t/t3032-merge-recursive-options.sh b/t/t3032-merge-recursive-options.sh
index de9ff89d14..44f5421be4 100755
--- a/t/t3032-merge-recursive-options.sh
+++ b/t/t3032-merge-recursive-options.sh
@@ -13,9 +13,12 @@ test_description='merge-recursive options
 
 . ./test-lib.sh
 
+test_have_prereq SED_STRIPS_CR && SED_OPTIONS=-b
+test_have_prereq MINGW && export GREP_OPTIONS=-U
+
 test_expect_success 'setup' '
 	conflict_hunks () {
-		sed -n -e "
+		sed $SED_OPTIONS -n -e "
 			/^<<<</ b conflict
 			b
 			: conflict
diff --git a/t/t6038-merge-text-auto.sh b/t/t6038-merge-text-auto.sh
index 460bf741b5..d9c2d386dd 100755
--- a/t/t6038-merge-text-auto.sh
+++ b/t/t6038-merge-text-auto.sh
@@ -14,7 +14,7 @@ test_description='CRLF merge conflict across text=auto change
 
 . ./test-lib.sh
 
-test_have_prereq MINGW && SED_OPTIONS=-b
+test_have_prereq SED_STRIPS_CR && SED_OPTIONS=-b
 
 test_expect_success setup '
 	git config core.autocrlf false &&
diff --git a/t/test-lib.sh b/t/test-lib.sh
index cb1ca973aa..42f2f14496 100644
--- a/t/test-lib.sh
+++ b/t/test-lib.sh
@@ -1057,6 +1057,13 @@ case $(uname -s) in
 	# backslashes in pathspec are converted to '/'
 	# exec does not inherit the PID
 	test_set_prereq MINGW
+	test_set_prereq SED_STRIPS_CR
+	;;
+*CYGWIN*)
+	test_set_prereq POSIXPERM
+	test_set_prereq EXECKEEPSPID
+	test_set_prereq NOT_MINGW
+	test_set_prereq SED_STRIPS_CR
 	;;
 *)
 	test_set_prereq POSIXPERM