diff --git a/tools/hitag2crack/crack3/ht2crack3.c b/tools/hitag2crack/crack3/ht2crack3.c
index 555c6d82a..917747820 100644
--- a/tools/hitag2crack/crack3/ht2crack3.c
+++ b/tools/hitag2crack/crack3/ht2crack3.c
@@ -325,7 +325,7 @@ int main(int argc, char *argv[]) {
 
     // set klowerstart (for debugging)
     if (argc > 3) {
-        klowerstart = strtol(argv[3], NULL, 0);
+        klowerstart = strtoull(argv[3], NULL, 0);
     } else {
         klowerstart = 0;
     }
diff --git a/tools/hitag2crack/crack3/ht2crack3test.c b/tools/hitag2crack/crack3/ht2crack3test.c
index ebf7b481d..17a1904e2 100644
--- a/tools/hitag2crack/crack3/ht2crack3test.c
+++ b/tools/hitag2crack/crack3/ht2crack3test.c
@@ -54,7 +54,7 @@ int main(int argc, char *argv[]) {
             }
             hitag2_init(&hstate, rev64(hexreversetouint64(key)), rev32(hexreversetouint32(uid)), rev32(hexreversetouint32(nr)));
 
-            arval = strtol(ar, NULL, 16);
+            arval = strtoul(ar, NULL, 16);
             ks = hitag2_nstep(&hstate, 32);
 
 
diff --git a/tools/hitag2crack/crack4/ht2crack4.c b/tools/hitag2crack/crack4/ht2crack4.c
index 83d2c92e7..eabb15227 100644
--- a/tools/hitag2crack/crack4/ht2crack4.c
+++ b/tools/hitag2crack/crack4/ht2crack4.c
@@ -325,7 +325,7 @@ static double bit_score(uint64_t s, uint64_t size, uint64_t b) {
 
 
     // chop away any bits beyond size
-    chopped = s & ((1l << size) - 1);
+    chopped = s & ((UINT64_C(1) << size) - 1);
     // and pack the remaining bits
     packed = packstate(chopped);
 
@@ -514,7 +514,7 @@ static void score_all_traces(unsigned int size) {
 
     // start the threads
     for (i = 0; i < NUM_THREADS; i++) {
-        if (pthread_create(&(threads[i]), NULL, score_some_traces, (void *)(tdata + i))) {
+        if (pthread_create(&(threads[i]), NULL, score_some_traces, (void *)(uintptr_t)(tdata + i))) {
             printf("cannot start thread %u\n", i);
             exit(1);
         }
@@ -555,7 +555,7 @@ static void expand_guesses(unsigned int halfsize, unsigned int size) {
     unsigned int i, j;
 
     for (i = 0; i < halfsize; i++) {
-        guesses[i + halfsize].key = guesses[i].key | (1l << size);
+        guesses[i + halfsize].key = guesses[i].key | (UINT64_C(1) << size);
         guesses[i + halfsize].score = guesses[i].score;
         for (j = 0; j < num_nRaR; j++) {
             guesses[i + halfsize].b0to31[j] = guesses[i].b0to31[j];
@@ -570,7 +570,7 @@ static void check_supplied_testkey(unsigned int size) {
     uint64_t partkey;
     unsigned int i;
 
-    partkey = supplied_testkey & ((1l << size) - 1);
+    partkey = supplied_testkey & ((UINT64_C(1) << size) - 1);
 
     for (i = 0; i < num_guesses; i++) {
         if (guesses[i].key == partkey) {
@@ -620,7 +620,12 @@ static void crack(void) {
 
         // print some metrics
         uint64_t revkey = rev64(guesses[0].key);
-        uint64_t foundkey = ((revkey >> 40) & 0xff) | ((revkey >> 24) & 0xff00) | ((revkey >> 8) & 0xff0000) | ((revkey << 8) & 0xff000000) | ((revkey << 24) & 0xff00000000) | ((revkey << 40) & 0xff0000000000);
+        uint64_t foundkey = ((revkey >> 40) & UINT64_C(0xff)) |
+                            ((revkey >> 24) & UINT64_C(0xff00)) |
+                            ((revkey >> 8) & UINT64_C(0xff0000)) |
+                            ((revkey << 8) & UINT64_C(0xff000000)) |
+                            ((revkey << 24) & UINT64_C(0xff00000000)) |
+                            ((revkey << 40) & UINT64_C(0xff0000000000));
         fprintf(stderr, " guess=%012" PRIx64 ", num_guesses = %u, top score=%1.10f, min score=%1.10f\n", foundkey, num_guesses, guesses[0].score, guesses[num_guesses - 1].score);
     }
 }
@@ -828,7 +833,12 @@ int main(int argc, char *argv[]) {
                 check_key(guesses[i].key, nonces[1].enc_nR, nonces[1].ks)) {
             printf("WIN!!! :)\n");
             revkey = rev64(guesses[i].key);
-            foundkey = ((revkey >> 40) & 0xff) | ((revkey >> 24) & 0xff00) | ((revkey >> 8) & 0xff0000) | ((revkey << 8) & 0xff000000) | ((revkey << 24) & 0xff00000000) | ((revkey << 40) & 0xff0000000000);
+            foundkey = ((revkey >> 40) & UINT64_C(0xff)) |
+                       ((revkey >> 24) & UINT64_C(0xff00)) |
+                       ((revkey >> 8) & UINT64_C(0xff0000)) |
+                       ((revkey << 8) & UINT64_C(0xff000000)) |
+                       ((revkey << 24) & UINT64_C(0xff00000000)) |
+                       ((revkey << 40) & UINT64_C(0xff0000000000));
             printf("key = %012" PRIX64 "\n", foundkey);
             exit(0);
         }
diff --git a/tools/hitag2crack/crack5/ht2crack5.c b/tools/hitag2crack/crack5/ht2crack5.c
index adec84ef2..39c59ac82 100644
--- a/tools/hitag2crack/crack5/ht2crack5.c
+++ b/tools/hitag2crack/crack5/ht2crack5.c
@@ -149,7 +149,7 @@ int main(int argc, char *argv[]) {
         nR1 = rev32(hexreversetouint32(argv[2]));
     }
 
-    aR1 = strtol(argv[3], NULL, 16);
+    aR1 = strtoul(argv[3], NULL, 16);
 
     if (!strncmp(argv[4], "0x", 2) || !strncmp(argv[4], "0X", 2)) {
         nR2 = rev32(hexreversetouint32(argv[4] + 2));
@@ -157,7 +157,7 @@ int main(int argc, char *argv[]) {
         nR2 = rev32(hexreversetouint32(argv[4]));
     }
 
-    aR2 = strtol(argv[5], NULL, 16);
+    aR2 = strtoul(argv[5], NULL, 16);
 
     target = ~aR1;
     // bitslice inverse target bits
diff --git a/tools/hitag2crack/crack5gpu_disabled/ht2crack5gpu.c b/tools/hitag2crack/crack5gpu_disabled/ht2crack5gpu.c
index e038e055e..fa80cd2c3 100644
--- a/tools/hitag2crack/crack5gpu_disabled/ht2crack5gpu.c
+++ b/tools/hitag2crack/crack5gpu_disabled/ht2crack5gpu.c
@@ -201,7 +201,7 @@ int main(int argc, char *argv[]) {
         nR1 = rev32(hexreversetouint32(argv[2]));
     }
 
-    aR1 = strtol(argv[3], NULL, 16);
+    aR1 = strtoul(argv[3], NULL, 16);
 
     if (!strncmp(argv[4], "0x", 2) || !strncmp(argv[4], "0X", 2)) {
         nR2 = rev32(hexreversetouint32(argv[4] + 2));
@@ -209,7 +209,7 @@ int main(int argc, char *argv[]) {
         nR2 = rev32(hexreversetouint32(argv[4]));
     }
 
-    aR2 = strtol(argv[5], NULL, 16);
+    aR2 = strtoul(argv[5], NULL, 16);
 
     target = ~aR1;
     // bitslice inverse target bits