diff --git a/src/cJSON/cJSON.c b/src/cJSON/cJSON.c
index 4c6a308e..ebd48668 100644
--- a/src/cJSON/cJSON.c
+++ b/src/cJSON/cJSON.c
@@ -78,8 +78,12 @@
 #endif
 
 #ifndef NAN
+#ifdef _WIN32
+#define NAN sqrt(-1.0)
+#else
 #define NAN 0.0/0.0
 #endif
+#endif
 
 typedef struct {
     const unsigned char *json;
@@ -113,7 +117,7 @@ CJSON_PUBLIC(double) cJSON_GetNumberValue(const cJSON * const item)
 }
 
 /* This is a safeguard to prevent copy-pasters from using incompatible C and header files */
-#if (CJSON_VERSION_MAJOR != 1) || (CJSON_VERSION_MINOR != 7) || (CJSON_VERSION_PATCH != 14)
+#if (CJSON_VERSION_MAJOR != 1) || (CJSON_VERSION_MINOR != 7) || (CJSON_VERSION_PATCH != 15)
     #error cJSON.h and cJSON.c have different versions. Make sure that both have the same.
 #endif
 
@@ -507,10 +511,8 @@ static unsigned char* ensure(printbuffer * const p, size_t needed)
 
             return NULL;
         }
-        if (newbuffer)
-        {
-            memcpy(newbuffer, p->buffer, p->offset + 1);
-        }
+        
+        memcpy(newbuffer, p->buffer, p->offset + 1);
         p->hooks.deallocate(p->buffer);
     }
     p->length = newsize;
@@ -2544,6 +2546,7 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateIntArray(const int *numbers, int count)
     }
 
     a = cJSON_CreateArray();
+
     for(i = 0; a && (i < (size_t)count); i++)
     {
         n = cJSON_CreateNumber(numbers[i]);
@@ -2562,7 +2565,10 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateIntArray(const int *numbers, int count)
         }
         p = n;
     }
-    a->child->prev = n;
+
+    if (a && a->child) {
+        a->child->prev = n;
+    }
 
     return a;
 }
@@ -2599,7 +2605,10 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateFloatArray(const float *numbers, int count)
         }
         p = n;
     }
-    a->child->prev = n;
+
+    if (a && a->child) {
+        a->child->prev = n;
+    }
 
     return a;
 }
@@ -2618,7 +2627,7 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateDoubleArray(const double *numbers, int count)
 
     a = cJSON_CreateArray();
 
-    for(i = 0;a && (i < (size_t)count); i++)
+    for(i = 0; a && (i < (size_t)count); i++)
     {
         n = cJSON_CreateNumber(numbers[i]);
         if(!n)
@@ -2636,7 +2645,10 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateDoubleArray(const double *numbers, int count)
         }
         p = n;
     }
-    a->child->prev = n;
+
+    if (a && a->child) {
+        a->child->prev = n;
+    }
 
     return a;
 }
@@ -2673,8 +2685,11 @@ CJSON_PUBLIC(cJSON *) cJSON_CreateStringArray(const char *const *strings, int co
         }
         p = n;
     }
-    a->child->prev = n;
 
+    if (a && a->child) {
+        a->child->prev = n;
+    }
+    
     return a;
 }
 
@@ -2961,7 +2976,7 @@ CJSON_PUBLIC(cJSON_bool) cJSON_IsRaw(const cJSON * const item)
 
 CJSON_PUBLIC(cJSON_bool) cJSON_Compare(const cJSON * const a, const cJSON * const b, const cJSON_bool case_sensitive)
 {
-    if ((a == NULL) || (b == NULL) || ((a->type & 0xFF) != (b->type & 0xFF)) || cJSON_IsInvalid(a))
+    if ((a == NULL) || (b == NULL) || ((a->type & 0xFF) != (b->type & 0xFF)))
     {
         return false;
     }
@@ -3092,4 +3107,4 @@ CJSON_PUBLIC(void *) cJSON_malloc(size_t size)
 CJSON_PUBLIC(void) cJSON_free(void *object)
 {
     global_hooks.deallocate(object);
-}
+}
\ No newline at end of file
diff --git a/src/cJSON/cJSON.h b/src/cJSON/cJSON.h
index e97e5f4c..8ff711b8 100644
--- a/src/cJSON/cJSON.h
+++ b/src/cJSON/cJSON.h
@@ -81,7 +81,7 @@ then using the CJSON_API_VISIBILITY flag to "export" the same symbols the way CJ
 /* project version */
 #define CJSON_VERSION_MAJOR 1
 #define CJSON_VERSION_MINOR 7
-#define CJSON_VERSION_PATCH 14
+#define CJSON_VERSION_PATCH 15
 
 #include <stddef.h>
 
@@ -256,7 +256,7 @@ CJSON_PUBLIC(cJSON_bool) cJSON_Compare(const cJSON * const a, const cJSON * cons
 
 /* Minify a strings, remove blank characters(such as ' ', '\t', '\r', '\n') from strings.
  * The input pointer json cannot point to a read-only address area, such as a string constant, 
- * but should point to a readable and writable adress area. */
+ * but should point to a readable and writable address area. */
 CJSON_PUBLIC(void) cJSON_Minify(char *json);
 
 /* Helper functions for creating and adding items to an object at the same time.
@@ -290,4 +290,4 @@ CJSON_PUBLIC(void) cJSON_free(void *object);
 }
 #endif
 
-#endif
+#endif
\ No newline at end of file