Index: test/util.c
--- test/util.c.orig	2021-08-13 20:55:40.000000000 +0200
+++ test/util.c	2021-08-28 09:53:44.780448000 +0200
@@ -49,7 +49,7 @@
 #include <stdint.h>
 
 /* include space for null terminator */
-static char bit_string[MAX_PRINT_STRING_LEN + 1];
+static char my_bit_string[MAX_PRINT_STRING_LEN + 1];
 
 static inline int hex_char_to_nibble(uint8_t c)
 {
@@ -157,11 +157,11 @@
     }
 
     for (i = 0; i < length; i += 2) {
-        bit_string[i] = nibble_to_hex_char(*str >> 4);
-        bit_string[i + 1] = nibble_to_hex_char(*str++ & 0xF);
+        my_bit_string[i] = nibble_to_hex_char(*str >> 4);
+        my_bit_string[i + 1] = nibble_to_hex_char(*str++ & 0xF);
     }
-    bit_string[i] = 0; /* null terminate string */
-    return bit_string;
+    my_bit_string[i] = 0; /* null terminate string */
+    return my_bit_string;
 }
 
 static const char b64chars[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
