diff --git a/tests/suites/test_suite_base64.function b/tests/suites/test_suite_base64.function
index 8775c8dfb..67fbb6750 100644
--- a/tests/suites/test_suite_base64.function
+++ b/tests/suites/test_suite_base64.function
@@ -4,7 +4,7 @@
 #include <test/constant_flow.h>
 
 #if defined(MBEDTLS_TEST_HOOKS)
-static const char digits[] =
+static const char base64_digits[] =
     "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
 #endif /* MBEDTLS_TEST_HOOKS */
 
@@ -45,7 +45,7 @@ void enc_chars( )
         unsigned char digit = mbedtls_base64_enc_char( value );
         TEST_CF_PUBLIC( &value, sizeof( value ) );
         TEST_CF_PUBLIC( &digit, sizeof( digit ) );
-        TEST_EQUAL( digit, digits[value] );
+        TEST_EQUAL( digit, base64_digits[value] );
     }
 }
 /* END_CASE */
@@ -59,12 +59,12 @@ void dec_chars( )
     for( unsigned c = 0; c <= 0xff; c++ )
     {
         mbedtls_test_set_step( c );
-        /* digits is 0-terminated. sizeof()-1 excludes the trailing 0. */
-        p = memchr( digits, c, sizeof( digits ) - 1 );
+        /* base64_digits is 0-terminated. sizeof()-1 excludes the trailing 0. */
+        p = memchr( base64_digits, c, sizeof( base64_digits ) - 1 );
         if( p == NULL )
             expected = -1;
         else
-            expected = p - digits;
+            expected = p - base64_digits;
         TEST_CF_SECRET( &c, sizeof( c ) );
         signed char actual = mbedtls_base64_dec_value( c );
         TEST_CF_PUBLIC( &c, sizeof( c ) );