one simple way to align memory alloc'ed

memory-align.c

/*
one simple way to align memory alloc'ed
based on sqlite3 macro

+7 = 8 (64-bit)
+3 = 4 (32-bit)

HINT: you can try ptrdiff_t too =)
*/

#include <stdio.h>
#define __align(x)  (((x)+7)&~7)

int main() {

    for (int i=0; i<19; i++) {
        printf("i=%d aligned=%d\n", i, __align(i));
    }

    return 0;
}

/* output: 

i=0 aligned=0
i=1 aligned=8
i=2 aligned=8
i=3 aligned=8
i=4 aligned=8
i=5 aligned=8
i=6 aligned=8
i=7 aligned=8
i=8 aligned=8
i=9 aligned=16
...
*/