diff --git a/tests/suites/helpers.function b/tests/suites/helpers.function
index 278de16..cd9346e 100644
--- a/tests/suites/helpers.function
+++ b/tests/suites/helpers.function
@@ -433,7 +433,7 @@
 }
 #endif /* __unix__ || __APPLE__ __MACH__ */
 
-int unhexify( unsigned char *obuf, const char *ibuf )
+int mbedtls_test_unhexify( unsigned char *obuf, const char *ibuf )
 {
     unsigned char c, c2;
     int len = strlen( ibuf ) / 2;
@@ -467,7 +467,7 @@
     return len;
 }
 
-void hexify( unsigned char *obuf, const unsigned char *ibuf, int len )
+void mbedtls_test_hexify( unsigned char *obuf, const unsigned char *ibuf, int len )
 {
     unsigned char l, h;
 
@@ -533,7 +533,7 @@
     obuf = mbedtls_calloc( 1, *olen );
     TEST_HELPER_ASSERT( obuf != NULL );
 
-    (void) unhexify( obuf, ibuf );
+    (void) mbedtls_test_unhexify( obuf, ibuf );
 
     return( obuf );
 }