diff --git a/tests/src/asn1_helpers.c b/tests/src/asn1_helpers.c
index c8df199..c63bd0c 100644
--- a/tests/src/asn1_helpers.c
+++ b/tests/src/asn1_helpers.c
@@ -15,6 +15,8 @@
 
 #include <mbedtls/asn1.h>
 
+#include <test/asn1_helpers.h>
+
 int mbedtls_test_asn1_skip_integer(unsigned char **p, const unsigned char *end,
                                    size_t min_bits, size_t max_bits,
                                    int must_be_odd)