C language: pointer returned by malloc() and casting
Possible Duplicate:
Do I cast the result of malloc?
What is the Best Practice for malloc?
Im new with c language and i have a question as i was explained in class:
The type of the pointer returned by malloc() is void *, and therefore we need to cast it into the required type
which means i need to do:
char *str;
str = (char *) malloc(14);
but i dont understand, is it a must? lets say malloc returns that void pointer, why do i see many of examples around without doing the casting? an example:
float *arr = malloc (20 * sizeof (float));
Could anyone please explain :) ?
In C, this cast is not required. The conversion is indeed implicit.
C11 (n1570), § 6.3.2.3 Pointers
A pointer to void may be converted to or from a pointer to any object type. A pointer to any object type may be converted to a pointer to void and back again; the result shall compare equal to the original pointer.
Since it is unecessary, cast malloc return or not is another question (see here).
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