Fixed a warning.

README.md

@@ -62,7 +62,7 @@ int main(void)
 API Reference
 =============
 
-This section describes the LibHashSet programming interface. The functions for managing *hash sets* are declared in `<hash_set.h>`, whereas the functions for managing to *hash maps* are declared  and `<hash_map.h>`.
+This section describes the LibHashSet programming interface. The functions for managing *hash sets* are declared in `<hash_set.h>`, whereas the functions for managing to *hash maps* are declared in `<hash_map.h>`.
 
 LibHashSet supports sets and maps containing elements of different integral types. For each element type, separate functions are provided. The functions for `uint16_t`, `uint32_t` and `uint64_t` can be distinguished by the suffix `…16`, `…32` and `…64`, respectively. In the following, the functions are described in their "generic" form.
 

example/hash-map/src/main.c

@@ -4,7 +4,6 @@
 /******************************************************************************/
 
 #include <hash_map.h>
-#include <hash_set.h>
 #include <stdio.h>
 #include <inttypes.h>
 #include "input.h"

libhashset/include/hash_map.h

@@ -23,8 +23,9 @@
 extern "C" {
 #endif
 
-#if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(_ERRNO_T_DEFINED)
+#if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(_LIBHASHSET_ERRNO_DEFINED)
 typedef int errno_t;
+#define _LIBHASHSET_ERRNO_DEFINED 1
 #endif
 
 /* ------------------------------------------------- */

libhashset/include/hash_set.h

@@ -23,8 +23,9 @@
 extern "C" {
 #endif
 
-#if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(_ERRNO_T_DEFINED)
+#if !defined(_MSC_VER) && !defined(__MINGW32__) && !defined(_LIBHASHSET_ERRNO_DEFINED)
 typedef int errno_t;
+#define _LIBHASHSET_ERRNO_DEFINED 1
 #endif
 
 /* ------------------------------------------------- */