diff --git a/tools/hitag2crack/crack2/ht2crack2buildtable.c b/tools/hitag2crack/crack2/ht2crack2buildtable.c
index 6533e3934..02273e680 100644
--- a/tools/hitag2crack/crack2/ht2crack2buildtable.c
+++ b/tools/hitag2crack/crack2/ht2crack2buildtable.c
@@ -354,7 +354,7 @@ static void makedirs(void) {
     }
 }
 
-static int datacmp(const void *p1, const void *p2, void *dummy) {
+static int datacmp(const void *p1, const void *p2) {
     unsigned char *d_1 = (unsigned char *)p1;
     unsigned char *d_2 = (unsigned char *)p2;
 
@@ -420,8 +420,7 @@ static void *sorttable(void *dd) {
             close(fdin);
 
             // sort it
-            void *dummy = NULL; // clang
-            qsort_r(table, numentries, DATASIZE, datacmp, dummy);
+            qsort(table, numentries, DATASIZE, datacmp);
 
             // write to file
             snprintf(outfile, sizeof(outfile), "sorted/%02x/%02x.bin", i, j);