Update khash.h to latest version

khash.h

@@ -151,6 +151,14 @@ typedef unsigned long long khint64_t;
 #endif
 #endif /* kh_inline */
 
+#ifndef klib_unused
+#if (defined __clang__ && __clang_major__ >= 3) || (defined __GNUC__ && __GNUC__ >= 3)
+#define klib_unused __attribute__ ((__unused__))
+#else
+#define klib_unused
+#endif
+#endif /* klib_unused */
+
 typedef khint32_t khint_t;
 typedef khint_t khiter_t;
 
@@ -184,7 +192,7 @@ typedef khint_t khiter_t;
 static const double __ac_HASH_UPPER = 0.77;
 
 #define __KHASH_TYPE(name, khkey_t, khval_t) \
-	typedef struct { \
+	typedef struct kh_##name##_s { \
 		khint_t n_buckets, size, n_occupied, upper_bound; \
 		khint32_t *flags; \
 		khkey_t *keys; \
@@ -355,7 +363,7 @@ static const double __ac_HASH_UPPER = 0.77;
 	__KHASH_IMPL(name, SCOPE, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 
 #define KHASH_INIT(name, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal) \
-	KHASH_INIT2(name, static kh_inline, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
+	KHASH_INIT2(name, static kh_inline klib_unused, khkey_t, khval_t, kh_is_map, __hash_func, __hash_equal)
 
 /* --- BEGIN OF HASH FUNCTIONS --- */
 
@@ -411,7 +419,7 @@ static kh_inline khint_t __ac_Wang_hash(khint_t key)
     key ^=  (key >> 16);
     return key;
 }
-#define kh_int_hash_func2(k) __ac_Wang_hash((khint_t)key)
+#define kh_int_hash_func2(key) __ac_Wang_hash((khint_t)key)
 
 /* --- END OF HASH FUNCTIONS --- */