Questions about C malloc function [duplicate]

Question

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Do I cast the result of malloc? (26 answers)

Closed 5 years ago.

Why do we cast malloc, as in the following?

ptd = (double *) malloc(max * sizeof(double));

What is malloc's normal return type? Why do we need to cast it?

Answer 1

From a standard guide:

Declaration:

void *malloc(size_t size);

Allocates the requested memory and returns a pointer to it. The requested size is size bytes. The value of the space is indeterminate. On success a pointer to the requested space is returned. On failure a null pointer is returned.

That should be everything!

Answer 2

This is malloc prototype

void *malloc(size_t size);

Generally no need to do typecasting.