Conflicting data types

[Burnt Marshmallow]

I'm receiving an error: "conflicting types for 'size'" and a warning: "passing argument 1 of 'size' fro incompatible pointer type". This occurs in many spots in my code, but here is an example of one of the things I'm having issues with:

int bst_size(struct bst* bst) {
return size(bst->root);
}

int size(struct bst_node* curNode){ //This is where I'm receiving the error
//stuff here that is irrelevant to my question
}


and here are my structs defined:

struct bst_node {
int val;
struct bst_node* left;
struct bst_node* right;
};

struct bst {
struct bst_node* root;
};

[Peter87]

Have you declared the size function previously? Make sure it has the correct return and parameter types in both places.

[coder777]

What you have here:

int bst_size(struct bst* bst) {

is a forward declaration. See:

http://en.cppreference.com/w/c/language/struct

So if bst is unknown at that time you cannot use one of its members.
Move the declaration of the structs before the first time you use it.