diff --git a/tests/tests-skeletons/check-INTEGER.c b/tests/tests-skeletons/check-INTEGER.c
index b25960d..5beff7d 100644
--- a/tests/tests-skeletons/check-INTEGER.c
+++ b/tests/tests-skeletons/check-INTEGER.c
@@ -26,7 +26,7 @@
 	long rlong = 123;
 
 	assert(buf);
-	assert(size >= 0);
+	assert(size > 0);
 
 	val.buf = buf;
 	val.size = size;
@@ -133,7 +133,7 @@
 	assert(shared_scratch_start < scratch + sizeof(scratch));
 	assert(ret == 0);
 	ret = snprintf(verify, sizeof(verify), "%lu", check_long);
-	assert(ret < sizeof(verify));
+	assert(ret < (int)sizeof(verify));
 	ret = strcmp(scratch, verify);
 	printf("         [%s] vs [%s]: %d%s\n",
 		scratch, verify, ret,
diff --git a/tests/tests-skeletons/check-OER-support.c b/tests/tests-skeletons/check-OER-support.c
index ab244b1..5433900 100644
--- a/tests/tests-skeletons/check-OER-support.c
+++ b/tests/tests-skeletons/check-OER-support.c
@@ -21,7 +21,7 @@
     size_t enc_len = 0;
     ssize_t enc_len_len = oer_serialize_length(length, fill_buffer, &enc_len);
     assert(enc_len_len > 0);
-    assert(enc_len == enc_len_len);
+    assert(enc_len == (size_t)enc_len_len);
 
     /* Deserialize */
     size_t recovered_length = 0;
@@ -31,7 +31,8 @@
     }
     ssize_t dec_len = oer_fetch_length(buffer, enc_len, &recovered_length);
     if(ok) {
-        assert(dec_len == enc_len);
+        assert(dec_len > 0);
+        assert((size_t)dec_len == enc_len);
         if(recovered_length != length) {
             fprintf(stderr,
                     "Round-trip failed %zu->%zu (encoded %zd, decoded %zd)\n",
diff --git a/tests/tests-skeletons/check-OIDs.c b/tests/tests-skeletons/check-OIDs.c
index fc87841..eb0a014 100644
--- a/tests/tests-skeletons/check-OIDs.c
+++ b/tests/tests-skeletons/check-OIDs.c
@@ -92,13 +92,13 @@
 	memset(arcs, 'A', sizeof(arcs));
     alen = RELATIVE_OID_get_arcs(oid, arcs, sizeof(arcs) / sizeof(arcs[0]));
     assert(alen > 0);
-	assert(alen == ck_len);
+	assert((size_t)alen == ck_len);
 
 	/*
 	 * Make sure they are equivalent.
 	 */
 	printf("RELATIVE_OID_get_arcs() => {");
-	for(i = 0; i < alen; i++) {
+	for(i = 0; i < (size_t)alen; i++) {
         printf(" %" PRIu32, arcs[i]);
         assert(arcs[i] == ck_buf[i]);
 	}
diff --git a/tests/tests-skeletons/check-PER-UniversalString.c b/tests/tests-skeletons/check-PER-UniversalString.c
index eeba584..8028221 100644
--- a/tests/tests-skeletons/check-PER-UniversalString.c
+++ b/tests/tests-skeletons/check-PER-UniversalString.c
@@ -51,7 +51,7 @@
                     uper_output_buffer, (enc.encoded + 7) / 8, 0, 0);
     int st_out_ct = asn_check_constraints(td, st_out, NULL, NULL);
     assert(st_out_ct == 0);
-    assert(dec.consumed == enc.encoded);
+    assert(dec.consumed == (size_t)enc.encoded);
     assert(st_in->size == st_out->size);
     assert(memcmp(st_in->buf, st_out->buf, st_in->size) == 0);
     assert(st_out->size == buflen);
diff --git a/tests/tests-skeletons/check-PER-support.c b/tests/tests-skeletons/check-PER-support.c
index 4a0d96f..608430c 100644
--- a/tests/tests-skeletons/check-PER-support.c
+++ b/tests/tests-skeletons/check-PER-support.c
@@ -8,7 +8,7 @@
         ssize_t may_write = uper_put_length(po, length, &need_eom);
         fprintf(stderr, "  put %zu\n", may_write);
         assert(may_write >= 0);
-        assert(may_write <= length);
+        assert((size_t)may_write <= length);
         assert(need_eom != 123);
         length -= may_write;
         if(need_eom) {