diff --git a/compat/crypt.h b/compat/crypt.h
index 5eba242c..6e9b51ff 100644
--- a/compat/crypt.h
+++ b/compat/crypt.h
@@ -26,10 +26,12 @@
 */
 
 #ifndef _ZLIB_H
-#  if (ZLIB_VERNUM < 0x1270)
+#  if (ZLIB_VERNUM & 0xf != 0xf) && (ZLIB_VERNUM < 0x1270)
+    /* Define z_crc_t in zlib 1.2.6 and less */
     typedef unsigned long z_crc_t;
-#  else
-    typedef uint32_t z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf == 0xf) && (ZLIB_VERNUM < 0x12df)
+    /* Define z_crc_t in zlib-ng 2.0.7 and less */
+    typedef unsigned int z_crc_t;
 #  endif
 #endif
 
diff --git a/mz_crypt.c b/mz_crypt.c
index 4c8d6596..2971f84c 100644
--- a/mz_crypt.c
+++ b/mz_crypt.c
@@ -34,11 +34,12 @@ int32_t mz_crypt_rand(uint8_t *buf, int32_t size) {
 
 uint32_t mz_crypt_crc32_update(uint32_t value, const uint8_t *buf, int32_t size) {
 #if defined(HAVE_ZLIB)
-   /* Define z_crc_t in zlib 1.2.5 and less or if using zlib-ng */
-#  if (ZLIB_VERNUM < 0x1270)
+#  if (ZLIB_VERNUM & 0xf != 0xf) && (ZLIB_VERNUM < 0x1270)
+    /* Define z_crc_t in zlib 1.2.6 and less */
     typedef unsigned long z_crc_t;
-#  else
-    typedef uint32_t z_crc_t;
+#  elif (ZLIB_VERNUM & 0xf == 0xf) && (ZLIB_VERNUM < 0x12df)
+    /* Define z_crc_t in zlib-ng 2.0.7 and less */
+    typedef unsigned int z_crc_t;
 #  endif
     return (uint32_t)ZLIB_PREFIX(crc32)((z_crc_t)value, buf, (uInt)size);
 #elif defined(HAVE_LZMA)