I am not sure if there is a bug, I just changed the order of some things and it worked. Maybe it was an order issue. Console did not give any error messages, even when I had a friend look at it and supply me a document of the console of what he ran.

It is a bug. Changing the order may have made it appear to go away for now, but it could pop back up later if you add more code or change existing code.

Change the code back so that the crash is occurring and debug the code properly. In other words, use the debugger. That's what it's for.

edit: One odd thing I just noticed in your code is that you are freeing memory in your render_text function that you are not allocating yourself, since you are passing literal strings to the function.

In response to LennyLen, could you show me what you notice or how I might fix it?

As mentioned by LennyLen you're freeing memory in render_text (the line: free(text);) that was never allocated with malloc or new. When you call a function with a literal string (example: function("hello")), it does not need to be freed. Also the function render_var calls render_text which frees the text string and then render_var tries to operate on that text afterwards with strlen(text). These things can lead to a crash.

So just remove the clean up part?

void thing(const char* text) { 
    // Do stuff with text

    free(text);
}

int main() {
    const char* a = "abc";
    const char b[] = "def"
    char* c = malloc(4);
    char* d = new char[4];

    sprintf(c,"ghi");
    sprintf(d,"jkl");
   
    thing("mno"); // No!
    thing(a);     // No!
    thing(b);     // No!
    thing(c);     // Okay
    thing(d);     // No!

    // free(c);
    // delete[] d;
}

ah I get it now