Are there pointers that are not compatible with each other?
So that they (pointers) would be compatible they shall be pointers to compatible types 2 For two pointer types to be compatible, both shall be identically qualified and both shall be pointers to compatible types. However types int or char on the one hand and type void on the other hand are not compatible types.
How to use incompatible pointer type in C-stack overflow?
1. …or a char *, unsigned char * or signed char * object, because there’s a special rule for those. In your prototype declaration , you said second argument as void** ,so you have to type cast double** to void** . Instead of this line success = dequeue (queueIn, &target);. Use it like this. Thanks for contributing an answer to Stack Overflow!
What happens when a pointer is converted to another type?
8 A pointer to a function of one type may be converted to a pointer to a function of another type and back again; the result shall compare equal to the original pointer. If a converted pointer is used to call a function whose type is not compatible with the referenced type, the behavior is undefined.
How are two function types to be compatible?
15 For two function types to be compatible, both shall specify compatible return types.146) Moreover, the parameter type lists, if both are present, shall agree in the number of parameters and in use of the ellipsis terminator; corresponding parameters shall have compatible types. In your functions parameters are declared as pointers.
Is there an initialization from incompatible pointer type warning?
GCC gives me an ‘Initialization from incompatible pointer type’ warning when I use this code (though the code works fine and does what it’s supposed to do, which is print all the elements of the array).
Can a void pointer be converted to a pointer?
Even though all other pointer types can be converted to and from void * without loss of information, the same is not true of void ** and other pointer-to-pointer types; if you dereference a void ** pointer, it needs to be pointing at a genuine void * object 1.
What happens if you assign different types of pointers?
Even worse, the size of different types of pointers may not be equal. Hence, if your function doesn’t know what type of pointer it should assign, it cannot just “put the data in the address”, because the size of the right pointer may be different from the size of the pointer it assign.
Can a pointer be cast to a void?
You’re passing your myAlloc function an int ** variable, but your function is written to accept a void ** variable. You can cast the pointer type in the function call like this: And now it compiles without warnings.
How are pointers declared in a function parameter?
In your functions parameters are declared as pointers. So that they (pointers) would be compatible they shall be pointers to compatible types 2 For two pointer types to be compatible, both shall be identically qualified and both shall be pointers to compatible types.