diff --git a/test/input.c b/test/input.c
index 88b6731..498eadd 100644
--- a/test/input.c
+++ b/test/input.c
@@ -41,6 +41,7 @@ TEST line_limit(void) {
 
 	libscomm_reset(&in);
 	ASSERT_EQ(libscomm_read(&in, &p, &l), LIBSCOMM_COMPLETE);
+	ASSERT_EQ(p, &s[LIBSCOMM_MAXBUF]);
 	PASS();
 }
 
@@ -60,6 +61,8 @@ TEST single_arg_too_large(void) {
 
 	libscomm_reset(&in);
 	ASSERT_EQ(libscomm_read(&in, &p, &l), LIBSCOMM_OVERFLOW);
+	ASSERT_EQ(p, &s[sizeof s - 1]);
+
 	ASSERT_EQ(in.len, 0);
 
 	/* state values are opaque. */
@@ -81,6 +84,7 @@ TEST arg_limit(void) {
 	ASSERT_EQ(libscomm_read(&in, &p, &l), LIBSCOMM_COMPLETE);
 	ASSERT_EQ(l.name, 0);
 	ASSERT_EQ(l.len, LIBSCOMM_MAXARG);
+	ASSERT_EQ(p, &s[sizeof s - 1]);
 
 	for (i = 1; i <= l.len; i++) {
 		sprintf(tbuf, " %d", i);
@@ -98,6 +102,7 @@ TEST too_many_arg(void) {
 
 	libscomm_reset(&in);
 	ASSERT_EQ(libscomm_read(&in, &p, &l), LIBSCOMM_ARG_OVERFLOW);
+	ASSERT_EQ(p, &s[sizeof s - 1]);
 	PASS();
 }