the malloc() function returns pointer of type void*. allocates memory in bytes according size_t value passed argument it. resulting allocation raw bytes can used data type in c(without casting).
can array type char declared within function returns void *, used data type resulting allocation of malloc?
for example,
#include <stdio.h> void *stat_mem(); int main(void) { //size : 10 * sizeof(int) int buf[] = { 1,2,3,4,5,6,7,8,9,10 }; int *p = stat_mem(); memcpy(p, buf, sizeof(buf)); (int n = 0; n < 10; n++) { printf("%d ", p[n]); } putchar('\n'); return 0; } void *stat_mem() { static char array[128]; return array; }
the declared type of static object array char. effective type of object it's declared type. effective type of static object cannot changed, remainder of program effective type of array char.
if try access value of object type not compatible with, or not on list1, behavior undefined.
your code tries access stored value of array using type int. type not compatible type char , not on list of exceptions, behavior undefined when read array using int pointer p:
printf("%d ", p[n]); 1 (quoted from: iso:iec 9899:201x 6.5 expressions 7 )
object shall have stored value accessed lvalue expression has 1 of following types:
— type compatible effective type of object,
— qualified version of type compatible effective type of object,
— type signed or unsigned type corresponding effective type of object,
— type signed or unsigned type corresponding qualified version of effective type of object,
— aggregate or union type includes 1 of aforementioned types among members (including, recursively, member of subaggregate or contained union), or
— character type.
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