diff --git a/fix16_unittests.c b/fix16_unittests.c
index 96b5a11..5f3f9fe 100644
--- a/fix16_unittests.c
+++ b/fix16_unittests.c
@@ -101,7 +101,7 @@ int fix16_unittests(void)
             #ifndef FIXMATH_NO_OVERFLOW
             if (result != fix16_overflow)
             {
-              printf("\n%d * %d overflow not detected!\n", a, b);
+              printf("\n%ld * %ld overflow not detected!\n", (long)a, (long)b);
               failures++;
             }
             #endif
@@ -109,8 +109,8 @@ int fix16_unittests(void)
             continue;
           }

-          printf("\n%d * %d = %d\n", a, b, result);
-          printf("%f * %f = %d\n", fa, fb, fresult);
+          printf("\n%ld * %ld = %ld\n", (long)a, (long)b, (long)result);
+          printf("%f * %f = %ld\n", fa, fb, (long)fresult);
           failures++;
         }
       }
@@ -176,7 +176,7 @@ int fix16_unittests(void)
             #ifndef FIXMATH_NO_OVERFLOW
             if (result != fix16_overflow)
             {
-              printf("\n%d / %d overflow not detected!\n", a, b);
+              printf("\n%ld / %ld overflow not detected!\n", (long)a, (long)b);
               failures++;
             }
             #endif
@@ -222,7 +222,7 @@ int fix16_unittests(void)
             #ifndef FIXMATH_NO_OVERFLOW
             if (result != fix16_overflow)
             {
-              printf("\n%d + %d overflow not detected!\n", a, b);
+              printf("\n%ld + %ld overflow not detected!\n", (long)a, (long)b);
               failures++;
             }
             #endif
@@ -230,8 +230,8 @@ int fix16_unittests(void)
             continue;
           }

-          printf("\n%d + %d = %d\n", a, b, result);
-          printf("%f + %f = %d\n", fa, fb, fresult);
+          printf("\n%ld + %ld = %ld\n", (long)a, (long)b, (long)result);
+          printf("%f + %f = %ld\n", fa, fb, (long)fresult);
           failures++;
         }
       }
@@ -268,7 +268,7 @@ int fix16_unittests(void)
             #ifndef FIXMATH_NO_OVERFLOW
             if (result != fix16_overflow)
             {
-              printf("\n%d - %d overflow not detected!\n", a, b);
+              printf("\n%ld - %ld overflow not detected!\n", (long)a, (long)b);
               failures++;
             }
             #endif
@@ -276,8 +276,8 @@ int fix16_unittests(void)
             continue;
           }

-          printf("\n%d - %d = %d\n", a, b, result);
-          printf("%f - %f = %d\n", fa, fb, fresult);
+          printf("\n%ld - %ld = %ld\n", (long)a, (long)b, (long)result);
+          printf("%f - %f = %ld\n", fa, fb, (long)fresult);
           failures++;
         }
       }
@@ -321,8 +321,8 @@ int fix16_unittests(void)

       if (delta(fresult, result) > max_delta)
       {
-        printf("\nfix16_sqrt(%d) = %d\n", a, result);
-        printf("sqrt(%f) = %d\n", fa, fresult);
+        printf("\nfix16_sqrt(%ld) = %ld\n", (long)a, (long)result);
+        printf("sqrt(%f) = %ld\n", fa, (long)fresult);
         failures++;
       }
     }
diff --git a/fix16_str_unittests.c b/fix16_str_unittests.c
index c70da60..c7df566 100644
--- a/fix16_str_unittests.c
+++ b/fix16_str_unittests.c
@@ -93,14 +93,14 @@ int fix16_str_unittests(void)

             if (strcmp(goodbuf, testbuf) != 0)
             {
-                printf("Value (fix16_t)%d gave %s, should be %s\n", value, testbuf, goodbuf);
+                printf("Value (fix16_t)%ld gave %s, should be %s\n", (long)value, testbuf, goodbuf);
                 ok = false;
             }

             fix16_t roundtrip = fix16_from_str(testbuf);
             if (roundtrip != value)
             {
-                printf("Roundtrip failed: (fix16_t)%d -> %s -> (fix16_t)%d\n", value, testbuf, roundtrip);
+                printf("Roundtrip failed: (fix16_t)%ld -> %s -> (fix16_t)%ld\n", (long)value, testbuf, (long)roundtrip);
                 ok = false;
             }

diff --git a/fix16_exp_unittests.c b/fix16_exp_unittests.c
index 01620df..658c873 100644
--- a/fix16_exp_unittests.c
+++ b/fix16_exp_unittests.c
@@ -41,7 +41,7 @@ int fix16_exp_unittests(void)
             count++;
         }

-        printf("Worst delta %d with input %d\n", max_delta, worst);
+        printf("Worst delta %ld with input %ld\n", (long)max_delta, (long)worst);
         printf("Average delta %0.2f\n", (float)sum / count);

         TEST(max_delta < 200);
@@ -80,7 +80,7 @@ int fix16_exp_unittests(void)
             count++;
         }

-        printf("Worst delta %0.4f%% with input %d\n", max_delta, worst);
+        printf("Worst delta %0.4f%% with input %ld\n", max_delta, (long)worst);
         printf("Average delta %0.4f%%\n", sum / count);

         TEST(max_delta < 1);
@@ -111,7 +111,7 @@ int fix16_exp_unittests(void)
             count++;
         }

-        printf("Worst delta %d with input %d\n", max_delta, worst);
+        printf("Worst delta %ld with input %ld\n", (long)max_delta, (long)worst);
         printf("Average delta %0.2f\n", (float)sum / count);

         TEST(max_delta < 20);