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[This ``longer explanation'' was provided by Mark Brader.]

In early C, [casts on malloc's return value] were not used. malloc() returned a char * value and this could be implicitly converted, as part of the = operator, to the desired pointer type. (In fact, in very early C, there was no cast operator and all conversions were implicit.)

Later on, implicit conversions of pointer types were seen as a bad thing, and the language was changed so that an = operator involving pointers needed the same type on both sides. Thus all pointer conversions now required an explicit cast. (In some compilers, the old-style implicit conversions still worked, but a warning would occur.)

Still later, with the coming of ANSI C, the type void * was introduced, malloc() was changed to return that type, and implicit pointer conversions went back into the language when void * was involved.

Therefore, the seemingly redundant casts are used by people who are


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